class FieldSwitchingLockinExperiment(Experiment):
""" Field Switching Experimen: measure resistance on Keithley while sweeping AMI430 field
"""
field = FloatParameter(default=0.0, unit="T")
# measure_current = FloatParameter(default=3e-6, unit="A")
resistance = OutputConnector(unit="Ohm")
res_reference = 1e3
vsource = 10e-3
mag = AMI430("192.168.5.109")
# keith = Keithley2400("GPIB0::25::INSTR")
lock = SR865("USB0::0xB506::0x2000::002638::INSTR")
def init_instruments(self):
# Initialize lockin
self.lock.amp = self.vsource
self.lock.tc = 3
self.mag.ramp()
self.delay = self.lock.measure_delay()
self.field.assign_method(self.mag.set_field)
self.field.add_post_push_hook(
lambda: time.sleep(0.1)) # Field set delay
time.sleep(self.delay)
async def run(self):
"""This is run for each step in a sweep."""
await asyncio.sleep(self.delay)
await self.resistance.push(self.res_reference /
((self.lock.amp / self.lock.mag) - 1.0))
def shutdown_instruments(self):
self.mag.zero()
self.lock.amp = 0
class FieldSwitchingLockinExperiment(Experiment):
""" Field Switching Experimen: measure resistance on Keithley while sweeping AMI430 field
"""
field = FloatParameter(default=0.0, unit="T")
resistance = OutputConnector(unit="Ohm")
# Default values for lockin measurement. These will need to be changed in a notebook to match the MR and switching current of the sample being measured
res_reference = 1e3
measure_current = 10e-6
fdB = 18
tc = 100e-3
mag = AMI430("192.168.5.109")
lock = SR865("USB0::0xB506::0x2000::002638::INSTR")
def init_instruments(self):
# Initialize lockin
self.lock.amp = self.res_reference*self.measure_current
self.lock.tc = self.tc
self.lock.filter_slope = self.fdB
self.mag.ramp()
self.delay = self.lock.measure_delay()
self.field.assign_method(self.mag.set_field)
self.field.add_post_push_hook(lambda: time.sleep(0.1)) # Field set delay
time.sleep(self.delay)
async def run(self):
"""This is run for each step in a sweep."""
await asyncio.sleep(self.delay)
await self.resistance.push(self.res_reference/((self.lock.amp/self.lock.mag)-1.0))
def shutdown_instruments(self):
self.mag.zero()
self.lock.amp = 0
class IcLockinExperiment(Experiment):
""" Nano-wire Ic measurement using Lockin with DC offset
"""
source = FloatParameter(default=0.0, unit="V")
voltage = OutputConnector(unit="V")
current = OutputConnector(unit="A")
resistance = OutputConnector(unit="Ohm")
R_ref = 1e3
sense = 5e-6
lock = SR865("USB0::0xB506::0x2000::002638::INSTR")
def init_instruments(self):
# self.keith.triad()
# self.keith.conf_meas_res(NPLC=10, res_range=1e5)
# self.keith.conf_src_curr(comp_voltage=0.5, curr_range=1.0e-5)
# self.keith.current = self.measure_current.value
# Initialize lockin
self.lock.amp = self.sense*self.R_ref
#self.lock.tc = self.integration_time
self.delay = self.lock.measure_delay()
# Define source method
self.source.assign_method(self.set_source)
#self.source.add_post_push_hook(lambda: time.sleep(2*self.integration_time))
def set_source(self,source):
self.lock.dc = source
time.sleep(self.lock.measure_delay())
async def run(self):
"""This is run for each step in a sweep."""
await asyncio.sleep(self.delay)
R_load = self.lock.mag/(self.sense - self.lock.mag)*self.R_ref
await self.resistance.push(R_load)
await self.current.push(self.lock.dc/(self.R_ref+R_load))
await self.voltage.push(self.lock.dc*R_load/(self.R_ref+R_load))
logger.debug("Stream has filled {} of {} points".format(self.resistance.points_taken,
self.resistance.num_points() ))
#await asyncio.sleep(2*self.integration_time) # Give the filters some time to catch up?
def shutdown_instruments(self):
self.lock.dc = 0
self.lock.amp = 0
class SwitchingExperiment(Experiment):
# Parameters and outputs
field = FloatParameter(default=0.0, unit="T")
pulse_duration = FloatParameter(default=5.0e-9, unit="s")
pulse_voltage = FloatParameter(default=0.1, unit="V")
voltage = OutputConnector()
# Constants (set with attribute access if you want to change these!)
attempts = 1 << 9
settle_delay = 100e-6
measure_current = 3.0e-6
samps_per_trig = 15
polarity = 1
pspl_atten = 4
min_daq_voltage = -1
max_daq_voltage = 1
reset_amplitude = 0.2
reset_duration = 5.0e-9
circuit_attenuation = 20.0
tc = 300e-6
# Instrument Resources
mag = AMI430("192.168.5.109")
lock = SR865("USB0::0xB506::0x2000::002638::INSTR")
pspl = Picosecond10070A("GPIB0::24::INSTR")
atten = Attenuator("calibration/RFSA2113SB_HPD_20160901.csv", lock.set_ao2,
lock.set_ao3)
arb = KeysightM8190A("192.168.5.108")
# keith = Keithley2400("GPIB0::25::INSTR")
def init_streams(self):
descrip = DataStreamDescriptor()
descrip.data_name = 'voltage'
descrip.add_axis(DataAxis("sample", range(self.samps_per_trig)))
descrip.add_axis(DataAxis("state", range(2)))
descrip.add_axis(DataAxis("attempt", range(self.attempts)))
self.voltage.set_descriptor(descrip)
def init_instruments(self):
self.lock.tc = self.tc
# Setup the Keithley
# self.keith.triad()
# self.keith.conf_meas_res(res_range=1e5)
# self.keith.conf_src_curr(comp_voltage=0.5, curr_range=1.0e-5)
# self.keith.current = self.measure_current
self.mag.ramp()
# Setup the AWG
self.arb.set_output(True, channel=1)
self.arb.set_output(False, channel=2)
self.arb.sample_freq = 12.0e9
self.arb.waveform_output_mode = "WSPEED"
self.arb.abort()
self.arb.delete_all_waveforms()
self.arb.reset_sequence_table()
self.arb.set_output_route("DC", channel=1)
self.arb.voltage_amplitude = 1.0
self.arb.set_marker_level_low(0.0, channel=1, marker_type="sync")
self.arb.set_marker_level_high(1.5, channel=1, marker_type="sync")
self.arb.continuous_mode = False
self.arb.gate_mode = False
def arb_pulse(amplitude, duration, sample_rate=12e9):
arb_voltage = arb_voltage_lookup()
pulse_points = int(duration * sample_rate)
if pulse_points < 320:
wf = np.zeros(320)
else:
wf = np.zeros(64 * np.ceil(pulse_points / 64.0))
wf[:pulse_points] = np.sign(amplitude) * arb_voltage(
abs(amplitude))
return wf
reset_wf = arb_pulse(
-self.polarity * self.reset_amplitude *
np.power(10.0, self.circuit_attenuation / 20.0),
self.reset_duration)
wf_data = KeysightM8190A.create_binary_wf_data(reset_wf)
rst_segment_id = self.arb.define_waveform(len(wf_data))
self.arb.upload_waveform(wf_data, rst_segment_id)
# no_reset_wf = arb_pulse(0.0, 3.0/12e9)
# wf_data = KeysightM8190A.create_binary_wf_data(no_reset_wf)
# no_rst_segment_id = self.arb.define_waveform(len(wf_data))
# self.arb.upload_waveform(wf_data, no_rst_segment_id)
# Picosecond trigger waveform
pspl_trig_wf = KeysightM8190A.create_binary_wf_data(np.zeros(3200),
samp_mkr=1)
pspl_trig_segment_id = self.arb.define_waveform(len(pspl_trig_wf))
self.arb.upload_waveform(pspl_trig_wf, pspl_trig_segment_id)
# NIDAQ trigger waveform
nidaq_trig_wf = KeysightM8190A.create_binary_wf_data(np.zeros(3200),
sync_mkr=1)
nidaq_trig_segment_id = self.arb.define_waveform(len(nidaq_trig_wf))
self.arb.upload_waveform(nidaq_trig_wf, nidaq_trig_segment_id)
settle_pts = int(640 * np.ceil(self.settle_delay * 12e9 / 640))
scenario = Scenario()
seq = Sequence(sequence_loop_ct=int(self.attempts))
#First try with reset flipping pulse
seq.add_waveform(rst_segment_id)
seq.add_idle(settle_pts, 0.0)
seq.add_waveform(nidaq_trig_segment_id)
seq.add_idle(1 << 16, 0.0) # bonus non-contiguous memory delay
seq.add_waveform(pspl_trig_segment_id)
seq.add_idle(settle_pts, 0.0)
seq.add_waveform(nidaq_trig_segment_id)
seq.add_idle(1 << 16, 0.0) # bonus non-contiguous memory delay
scenario.sequences.append(seq)
self.arb.upload_scenario(scenario, start_idx=0)
self.arb.sequence_mode = "SCENARIO"
self.arb.scenario_advance_mode = "REPEAT"
self.arb.scenario_start_index = 0
self.arb.run()
# Setup the NIDAQ
self.analog_input = Task()
self.read = int32()
self.buf_points = 2 * self.samps_per_trig * self.attempts
self.analog_input.CreateAIVoltageChan("Dev1/ai0", "", DAQmx_Val_Diff,
self.min_daq_voltage,
self.max_daq_voltage,
DAQmx_Val_Volts, None)
self.analog_input.CfgSampClkTiming("", 1e6, DAQmx_Val_Rising,
DAQmx_Val_FiniteSamps,
self.samps_per_trig)
self.analog_input.CfgInputBuffer(self.buf_points)
self.analog_input.CfgDigEdgeStartTrig("/Dev1/PFI0", DAQmx_Val_Rising)
self.analog_input.SetStartTrigRetriggerable(1)
self.analog_input.StartTask()
# Setup the PSPL
self.pspl.amplitude = self.polarity * 7.5 * np.power(
10, (-self.pspl_atten) / 20.0)
self.pspl.trigger_source = "EXT"
self.pspl.trigger_level = 0.1
self.pspl.output = True
def set_voltage(voltage):
# Calculate the voltage controller attenuator setting
vc_atten = abs(20.0 * np.log10(abs(voltage) / 7.5)
) - self.pspl_atten - self.circuit_attenuation
if vc_atten <= 6.0:
raise ValueError(
"Voltage controlled attenuation under range (6dB).")
self.atten.set_attenuation(vc_atten)
time.sleep(0.02)
# Assign methods
self.field.assign_method(self.mag.set_field)
self.pulse_duration.assign_method(self.pspl.set_duration)
self.pulse_voltage.assign_method(set_voltage)
# Create hooks for relevant delays
self.pulse_duration.add_post_push_hook(lambda: time.sleep(0.1))
async def run(self):
"""This is run for each step in a sweep."""
self.arb.advance()
self.arb.trigger()
buf = np.empty(self.buf_points)
self.analog_input.ReadAnalogF64(self.buf_points, -1,
DAQmx_Val_GroupByChannel, buf,
self.buf_points, byref(self.read),
None)
await self.voltage.push(buf)
# Seemingly we need to give the filters some time to catch up here...
await asyncio.sleep(0.02)
logger.debug("Stream has filled {} of {} points".format(
self.voltage.points_taken, self.voltage.num_points()))
def shutdown_instruments(self):
# self.keith.current = 0.0e-5
# self.mag.zero()
self.arb.stop()
self.pspl.output = False
try:
self.analog_input.StopTask()
except Exception as e:
print(
"Warning: failed to stop task (this normally happens with no consequences when taking multiple samples per trigger)."
)
pass
class ResetSearchExperiment(Experiment):
voltage = OutputConnector()
field = FloatParameter(default=0, unit="T")
duration = FloatParameter(default=5e-9, unit="s")
repeats = 200
amplitudes = np.arange(-0.01, 0.011, 0.01) # Reset amplitudes
samps_per_trig = 5
settle_delay = 50e-6
measure_current = 3e-6
# Instruments
arb = KeysightM8190A("192.168.5.108")
mag = AMI430("192.168.5.109")
keith = Keithley2400("GPIB0::25::INSTR")
lock = SR865("USB0::0xB506::0x2000::002638::INSTR")
polarity = -1
def init_streams(self):
# Baked in data axes
descrip = DataStreamDescriptor()
descrip.data_name = 'voltage'
descrip.add_axis(DataAxis("sample", range(self.samps_per_trig)))
descrip.add_axis(DataAxis("amplitude", self.amplitudes))
descrip.add_axis(DataAxis("repeat", range(self.repeats)))
self.voltage.set_descriptor(descrip)
def init_instruments(self):
# Set up Keithley
self.keith.triad()
self.keith.conf_meas_res(res_range=1e6)
self.keith.conf_src_curr(comp_voltage=0.6, curr_range=1.0e-5)
self.keith.current = self.measure_current
self.mag.ramp()
self.arb.set_output(True, channel=1)
self.arb.set_output(False, channel=2)
self.arb.sample_freq = 12.0e9
self.arb.waveform_output_mode = "WSPEED"
self.setup_AWG()
self.analog_input = Task()
self.read = int32()
self.buf_points = len(
self.amplitudes) * self.samps_per_trig * self.repeats
self.analog_input.CreateAIVoltageChan("Dev1/ai1", "", DAQmx_Val_Diff,
0.0, 0.5, DAQmx_Val_Volts, None)
self.analog_input.CfgSampClkTiming("", 1e6, DAQmx_Val_Rising,
DAQmx_Val_FiniteSamps,
self.samps_per_trig)
self.analog_input.CfgInputBuffer(self.buf_points)
self.analog_input.CfgDigEdgeStartTrig("/Dev1/PFI0", DAQmx_Val_Rising)
self.analog_input.SetStartTrigRetriggerable(1)
self.analog_input.StartTask()
# Assign methods
self.field.assign_method(self.mag.set_field)
self.duration.assign_method(self.setup_AWG)
def setup_AWG(self, *args):
self.arb.abort()
self.arb.delete_all_waveforms()
self.arb.reset_sequence_table()
self.arb.set_output_route("DC", channel=1)
self.arb.voltage_amplitude = 1.0
self.arb.set_marker_level_low(0.0, channel=1, marker_type="sync")
self.arb.set_marker_level_high(1.5, channel=1, marker_type="sync")
self.arb.continuous_mode = False
self.arb.gate_mode = False
def arb_pulse(amplitude, sample_rate=12e9):
pulse_points = int(self.duration.value * sample_rate)
if pulse_points < 320:
wf = np.zeros(320)
else:
wf = np.zeros(64 * int(np.ceil(pulse_points / 64.0)))
wf[:pulse_points] = amplitude
return wf
segment_ids = []
arb_voltage = arb_voltage_lookup()
for amp in self.amplitudes:
waveform = arb_pulse(np.sign(amp) * arb_voltage(abs(amp)))
wf_data = KeysightM8190A.create_binary_wf_data(waveform)
segment_id = self.arb.define_waveform(len(wf_data))
segment_ids.append(segment_id)
self.arb.upload_waveform(wf_data, segment_id)
# NIDAQ trigger waveform
nidaq_trig_wf = KeysightM8190A.create_binary_wf_data(np.zeros(3200),
sync_mkr=1)
nidaq_trig_segment_id = self.arb.define_waveform(len(nidaq_trig_wf))
self.arb.upload_waveform(nidaq_trig_wf, nidaq_trig_segment_id)
settle_pts = int(640 * np.ceil(self.settle_delay * 12e9 / 640))
start_idxs = [0]
scenario = Scenario()
seq = Sequence(sequence_loop_ct=int(self.repeats))
for si in segment_ids:
# seq = Sequence(sequence_loop_ct=int(1))
seq.add_waveform(si) # Apply switching pulse to the sample
seq.add_idle(settle_pts, 0.0) # Wait for the measurement to settle
seq.add_waveform(
nidaq_trig_segment_id) # Trigger the NIDAQ measurement
seq.add_idle(1 << 14, 0.0) # bonus non-contiguous memory delay
scenario.sequences.append(seq)
self.arb.upload_scenario(scenario, start_idx=start_idxs[-1])
start_idxs.append(start_idxs[-1] + len(scenario.scpi_strings()))
# The last entry is eroneous
start_idxs = start_idxs[:-1]
self.arb.sequence_mode = "SCENARIO"
self.arb.scenario_advance_mode = "REPEAT"
self.arb.stop()
self.arb.scenario_start_index = 0
self.arb.run()
async def run(self):
# Establish buffers
buffers = np.empty(self.buf_points)
self.arb.advance()
self.arb.trigger()
self.analog_input.ReadAnalogF64(self.buf_points, -1,
DAQmx_Val_GroupByChannel,
buffers, self.buf_points,
byref(self.read), None)
logger.debug("Read a buffer of {} points".format(buffers.size))
await self.voltage.push(buffers)
# Seemingly we need to give the filters some time to catch up here...
await asyncio.sleep(0.02)
logger.debug("Stream has filled {} of {} points".format(
self.voltage.points_taken, self.voltage.num_points()))
def shutdown_instruments(self):
try:
self.analog_input.StopTask()
except Exception as e:
logger.warning("Warning failed to stop task. This is typical.")
pass
self.arb.stop()
self.keith.current = 0.0
self.mag.disconnect()
class SwitchSearchLockinExperiment(Experiment):
voltage = OutputConnector()
sample = "CSHE2"
comment = "Search PSPL Switch Voltage"
# PARAMETERS: Confirm these before running
field = FloatParameter(default=0.0, unit="T")
pulse_voltage = FloatParameter(default=0, unit="V")
pulse_duration = FloatParameter(default=5.0e-9, unit="s")
measure_current = 3e-6
circuit_attenuation = 20.0
pspl_base_attenuation = 30.0
settle_delay = 100e-6
attempts = 1 << 8 # Number of attemps
samps_per_trig = 10 # Samples per trigger
# Instruments
arb = KeysightM8190A("192.168.5.108")
pspl = Picosecond10070A("GPIB0::24::INSTR")
mag = AMI430("192.168.5.109")
# keith = Keithley2400("GPIB0::25::INSTR")
lock = SR865("USB0::0xB506::0x2000::002638::INSTR")
atten = Attenuator("calibration/RFSA2113SB_HPD_20160901.csv", lock.set_ao2, lock.set_ao3)
min_daq_voltage = -10
max_daq_voltage = 10
def init_instruments(self):
# ===================
# Setup the Lockin
# ===================
self.lock.tc = 30e-6
time.sleep(0.5)
# self.keith.triad()
# self.keith.conf_meas_res(res_range=1e5)
# self.keith.conf_src_curr(comp_voltage=0.5, curr_range=1.0e-5)
# self.keith.current = self.measure_current
self.mag.ramp()
# ===================
# Setup the AWG
# ===================
self.arb.set_output(True, channel=1)
self.arb.set_output(False, channel=2)
self.arb.sample_freq = 12.0e9
self.arb.waveform_output_mode = "WSPEED"
self.arb.set_output_route("DC", channel=1)
self.arb.voltage_amplitude = 1.0
self.arb.set_marker_level_low(0.0, channel=1, marker_type="sync")
self.arb.set_marker_level_high(1.5, channel=1, marker_type="sync")
self.arb.continuous_mode = False
self.arb.gate_mode = False
# ===================
# Setup the PSPL
# ===================
self.pspl.amplitude = 7.5*np.power(10, -self.pspl_base_attenuation/20.0)
self.pspl.trigger_source = "EXT"
self.pspl.trigger_level = 0.1
self.pspl.output = True
self.setup_daq()
def set_voltage(voltage):
# Calculate the voltage controller attenuator setting
self.pspl.amplitude = np.sign(voltage)*7.5*np.power(10, -self.pspl_base_attenuation/20.0)
vc_atten = abs(20.0 * np.log10(abs(voltage)/7.5)) - self.pspl_base_attenuation - self.circuit_attenuation
if vc_atten <= 6.0:
logger.error("Voltage controlled attenuation under range (6dB).")
raise ValueError("Voltage controlled attenuation under range (6dB).")
self.atten.set_attenuation(vc_atten)
time.sleep(0.02)
# Assign methods
self.field.assign_method(self.mag.set_field)
self.pulse_duration.assign_method(self.pspl.set_duration)
self.pulse_voltage.assign_method(set_voltage)
# Create hooks for relevant delays
self.pulse_duration.add_post_push_hook(lambda: time.sleep(0.1))
def setup_daq(self):
self.arb.abort()
self.arb.delete_all_waveforms()
self.arb.reset_sequence_table()
# Picosecond trigger waveform
pspl_trig_wf = KeysightM8190A.create_binary_wf_data(np.zeros(3200), samp_mkr=1)
pspl_trig_segment_id = self.arb.define_waveform(len(pspl_trig_wf))
self.arb.upload_waveform(pspl_trig_wf, pspl_trig_segment_id)
# NIDAQ trigger waveform
nidaq_trig_wf = KeysightM8190A.create_binary_wf_data(np.zeros(3200), sync_mkr=1)
nidaq_trig_segment_id = self.arb.define_waveform(len(nidaq_trig_wf))
self.arb.upload_waveform(nidaq_trig_wf, nidaq_trig_segment_id)
settle_pts = int(640*np.ceil(self.settle_delay * 12e9 / 640))
scenario = Scenario()
seq = Sequence(sequence_loop_ct=int(self.attempts))
seq.add_waveform(pspl_trig_segment_id)
seq.add_idle(settle_pts, 0.0)
seq.add_waveform(nidaq_trig_segment_id)
seq.add_idle(1 << 16, 0.0) # bonus non-contiguous memory delay
scenario.sequences.append(seq)
self.arb.upload_scenario(scenario, start_idx=0)
self.arb.sequence_mode = "SCENARIO"
self.arb.scenario_advance_mode = "REPEAT"
self.arb.scenario_start_index = 0
self.arb.run()
# ===================
# Setup the NIDAQ
# ===================
self.analog_input = Task()
self.read = int32()
self.buf_points = self.samps_per_trig*self.attempts
self.analog_input.CreateAIVoltageChan("Dev1/ai0", "", DAQmx_Val_Diff,
self.min_daq_voltage, self.max_daq_voltage, DAQmx_Val_Volts, None)
self.analog_input.CfgSampClkTiming("", 1e6, DAQmx_Val_Rising, DAQmx_Val_FiniteSamps , self.samps_per_trig)
self.analog_input.CfgInputBuffer(self.buf_points)
self.analog_input.CfgDigEdgeStartTrig("/Dev1/PFI0", DAQmx_Val_Rising)
self.analog_input.SetStartTrigRetriggerable(1)
self.analog_input.StartTask()
def init_streams(self):
# Baked in data axes
descrip = DataStreamDescriptor()
descrip.add_axis(DataAxis("sample", range(self.samps_per_trig)))
descrip.add_axis(DataAxis("attempts", range(self.attempts)))
self.voltage.set_descriptor(descrip)
async def run(self):
self.arb.advance()
self.arb.trigger()
buf = np.empty(self.buf_points)
self.analog_input.ReadAnalogF64(self.buf_points, -1, DAQmx_Val_GroupByChannel,
buf, self.buf_points, byref(self.read), None)
logger.debug("Read a buffer of {} points".format(buf.size))
await self.voltage.push(buf)
# Seemingly we need to give the filters some time to catch up here...
await asyncio.sleep(0.02)
logger.debug("Stream has filled {} of {} points".format(self.voltage.points_taken, self.voltage.num_points()))
def shutdown_instruments(self):
try:
self.analog_input.StopTask()
except Exception as e:
logger.warning("Warning failed to stop task, which is quite typical (!)")
self.arb.stop()
# self.keith.current = 0.0
# self.mag.zero()
self.pspl.output = False
class SWERExperiment(Experiment):
""" Experiment class for Switching probability measurment
Determine switching probability for V << V0
with varying V (and durations?)
"""
field = FloatParameter(default=0.0, unit="T")
pulse_duration = FloatParameter(default=1.0e-9, unit="s")
pulse_voltage = FloatParameter(default=0.1, unit="V")
repeats = IntParameter(default = 1) # Dummy parameter for repeating
voltage = OutputConnector()
attempts = 1 << 12
settle_delay = 100e-6
measure_current = 3.0e-6
samps_per_trig = 5
polarity = 1
min_daq_voltage = 0.0
max_daq_voltage = 0.4
reset_amplitude = 0.1
reset_duration = 5.0e-9
mag = AMI430("192.168.5.109")
lock = SR865("USB0::0xB506::0x2000::002638::INSTR")
# pspl = Picosecond10070A("GPIB0::24::INSTR")
arb = KeysightM8190A("192.168.5.108")
keith = Keithley2400("GPIB0::25::INSTR")
def init_streams(self):
# Baked in data axes
descrip = DataStreamDescriptor()
descrip.add_axis(DataAxis("sample", range(self.samps_per_trig)))
descrip.add_axis(DataAxis("state", range(2)))
descrip.add_axis(DataAxis("attempt", range(self.attempts)))
self.voltage.set_descriptor(descrip)
def init_instruments(self):
# ===================
# Setup the Keithley
# ===================
self.keith.triad()
self.keith.conf_meas_res(res_range=1e5)
self.keith.conf_src_curr(comp_voltage=0.5, curr_range=1.0e-5)
self.keith.current = self.measure_current
self.mag.ramp()
# ===================
# Setup the AWG
# ===================
self.arb.set_output(True, channel=1)
self.arb.set_output(False, channel=2)
self.arb.sample_freq = 12.0e9
self.arb.waveform_output_mode = "WSPEED"
self.arb.set_output_route("DC", channel=1)
self.arb.voltage_amplitude = 1.0
self.arb.set_marker_level_low(0.0, channel=1, marker_type="sync")
self.arb.set_marker_level_high(1.5, channel=1, marker_type="sync")
self.arb.continuous_mode = False
self.arb.gate_mode = False
self.setup_arb(self.pulse_voltage.value)
# ===================
# Setup the NIDAQ
# ===================
self.analog_input = Task()
self.read = int32()
self.buf_points = 2*self.samps_per_trig*self.attempts
self.analog_input.CreateAIVoltageChan("Dev1/ai1", "", DAQmx_Val_Diff,
self.min_daq_voltage, self.max_daq_voltage, DAQmx_Val_Volts, None)
self.analog_input.CfgSampClkTiming("", 1e6, DAQmx_Val_Rising, DAQmx_Val_FiniteSamps , self.samps_per_trig)
self.analog_input.CfgInputBuffer(self.buf_points)
self.analog_input.CfgDigEdgeStartTrig("/Dev1/PFI0", DAQmx_Val_Rising)
self.analog_input.SetStartTrigRetriggerable(1)
self.analog_input.StartTask()
# Assign methods
self.field.assign_method(self.mag.set_field)
self.pulse_voltage.assign_method(self.setup_arb)
def setup_arb(self,volt):
def arb_pulse(amplitude, duration, sample_rate=12e9):
arb_voltage = arb_voltage_lookup()
pulse_points = int(duration*sample_rate)
if pulse_points < 320:
wf = np.zeros(320)
else:
wf = np.zeros(64*np.ceil(pulse_points/64.0))
wf[:pulse_points] = np.sign(amplitude)*arb_voltage(abs(amplitude))
return wf
self.arb.abort()
self.arb.delete_all_waveforms()
self.arb.reset_sequence_table()
# Reset waveform
reset_wf = arb_pulse(-self.polarity*self.reset_amplitude, self.reset_duration)
wf_data = KeysightM8190A.create_binary_wf_data(reset_wf)
rst_segment_id = self.arb.define_waveform(len(wf_data))
self.arb.upload_waveform(wf_data, rst_segment_id)
# Switching waveform
switch_wf = arb_pulse(self.polarity*volt, self.pulse_duration.value)
wf_data = KeysightM8190A.create_binary_wf_data(switch_wf)
sw_segment_id = self.arb.define_waveform(len(wf_data))
self.arb.upload_waveform(wf_data, sw_segment_id)
# NIDAQ trigger waveform
nidaq_trig_wf = KeysightM8190A.create_binary_wf_data(np.zeros(3200), sync_mkr=1)
nidaq_trig_segment_id = self.arb.define_waveform(len(nidaq_trig_wf))
self.arb.upload_waveform(nidaq_trig_wf, nidaq_trig_segment_id)
settle_pts = int(640*np.ceil(self.settle_delay * 12e9 / 640))
scenario = Scenario()
seq = Sequence(sequence_loop_ct=int(self.attempts))
#First try with reset flipping pulse
seq.add_waveform(rst_segment_id)
seq.add_idle(settle_pts, 0.0)
seq.add_waveform(nidaq_trig_segment_id)
seq.add_idle(1 << 16, 0.0) # bonus non-contiguous memory delay
seq.add_waveform(sw_segment_id)
seq.add_idle(settle_pts, 0.0)
seq.add_waveform(nidaq_trig_segment_id)
seq.add_idle(1 << 16, 0.0) # bonus non-contiguous memory delay
scenario.sequences.append(seq)
self.arb.upload_scenario(scenario, start_idx=0)
self.arb.sequence_mode = "SCENARIO"
self.arb.scenario_advance_mode = "REPEAT"
self.arb.scenario_start_index = 0
self.arb.run()
async def run(self):
# Keep track of the previous values
logger.debug("Waiting for filters.")
await asyncio.sleep(1.0)
self.arb.advance()
self.arb.trigger()
buf = np.empty(self.buf_points)
self.analog_input.ReadAnalogF64(self.buf_points, -1, DAQmx_Val_GroupByChannel,
buf, self.buf_points, byref(self.read), None)
await self.voltage.push(buf)
# Seemingly we need to give the filters some time to catch up here...
await asyncio.sleep(0.002)
logger.debug("Stream has filled {} of {} points".format(self.voltage.points_taken, self.voltage.num_points() ))
def shutdown_instruments(self):
self.keith.current = 0.0e-5
# self.mag.zero()
self.arb.stop()
try:
self.analog_input.StopTask()
except Exception as e:
print("Warning: failed to stop task (this normally happens with no consequences when taking multiple samples per trigger).")
pass
class nTronSwitchingExperimentFast(Experiment):
# Parameters and outputs
# channel_bias = FloatParameter(default=100e-6, unit="A") # On the 33220A
pulse_duration = FloatParameter(default=5.0e-9, unit="s")
pulse_voltage = FloatParameter(default=1, unit="V")
channel_bias = FloatParameter(default=500e-6, unit="A")
voltage = OutputConnector()
# Constants (set with attribute access if you want to change these!)
attempts = 1 << 6
# Reference resistances and attenuations
matching_ref_res = 50
chan_bias_ref_res = 1e4
pspl_base_attenuation = 10
circuit_attenuation = 0
pulse_polarity = 1
# Min/Max NIDAQ AI Voltage
min_daq_voltage = 0
max_daq_voltage = 10
# Measurement Sequence timing, clocks in Hz times in seconds
ai_clock = 0.25e6
do_clock = 0.5e6
trig_interval = 0.2e-3 # The repetition rate for switching attempts
bias_pulse_width = 40e-6 # This is how long the bias pulse is
pspl_trig_time = 4e-6 # When we trigger the gate pulse
integration_time = 20e-6 # How long to measure for
ai_delay = 2e-6 # How long before the measurement begins
# Instrument resources, NIDAQ called via PyDAQmx
arb_cb = Agilent33220A("192.168.5.199") # Channel Bias
pspl = Picosecond10070A("GPIB0::24::INSTR") # Gate Pulse
atten = RFMDAttenuator(
"calibration/RFSA2113SB_HPD_20160901.csv") # Gate Amplitude control
lock = SR865(
"USB0::0xB506::0x2000::002638::INSTR") # Gate Amplitude control
def init_instruments(self):
# Channel bias arb
self.arb_cb.output = False
self.arb_cb.load_resistance = (self.chan_bias_ref_res +
self.matching_ref_res)
self.arb_cb.function = 'Pulse'
self.arb_cb.pulse_period = 0.99 * self.trig_interval # Slightly under the trig interval since we are driving with another instrument
self.arb_cb.pulse_width = self.bias_pulse_width
self.arb_cb.pulse_edge = 100e-9 # Going through the DC port of a bias-tee, no need for fast edges
self.arb_cb.low_voltage = 0.0
self.arb_cb.high_voltage = self.channel_bias.value * (
self.chan_bias_ref_res + self.matching_ref_res)
self.arb_cb.burst_state = True
self.arb_cb.burst_cycles = 1
self.arb_cb.trigger_source = "External"
self.arb_cb.burst_mode = "Triggered"
self.arb_cb.output = True
self.arb_cb.polarity = 1
# Setup the NIDAQ
DAQmxResetDevice("Dev1")
measure_points = int(self.integration_time * self.ai_clock)
self.nidaq = CallbackTask(
asyncio.get_event_loop(),
measure_points,
self.attempts,
self.voltage,
# chunk_size=measure_points*(self.attempts>>2),
min_voltage=self.min_daq_voltage,
max_voltage=self.max_daq_voltage,
ai_clock=self.ai_clock)
self.nidaq.StartTask()
# Setup DO Triggers, P1:0 triggers AWG, P1:1 triggers PSPL and DAQ analog input
self.digital_output = Task()
data_p0 = np.zeros(int(self.do_clock * self.trig_interval),
dtype=np.uint8)
data_p0[0] = 1
data_p1 = np.zeros(int(self.do_clock * self.trig_interval),
dtype=np.uint8)
data_p1[int(self.do_clock * (self.pspl_trig_time))] = 1
data = np.append(data_p0, data_p1)
self.digital_output.CreateDOChan("/Dev1/port0/line0:1", "",
DAQmx_Val_ChanPerLine)
self.digital_output.CfgSampClkTiming(
"", self.do_clock, DAQmx_Val_Rising, DAQmx_Val_FiniteSamps,
int(data.size / 2) * self.attempts)
self.digital_output.WriteDigitalLines(
int(self.do_clock * self.trig_interval), 0, 1,
DAQmx_Val_GroupByChannel, data, None, None)
# Setup the PSPL`
self.pspl.amplitude = 7.5 * np.power(
10, (-self.pspl_base_attenuation) / 20.0)
self.pspl.trigger_source = "EXT"
self.pspl.trigger_level = 0.5
self.pspl.output = True
# Setup PSPL Attenuator Control
self.atten.set_supply_method(self.lock.set_ao2)
self.atten.set_control_method(self.lock.set_ao3)
# Setup bias current method
def set_bias(value):
self.arb_cb.high_voltage = self.channel_bias.value * (
self.chan_bias_ref_res + self.matching_ref_res)
self.arb_cb.low_voltage = 0.0
self.channel_bias.assign_method(set_bias)
def set_voltage(voltage, base_atten=self.pspl_base_attenuation):
# Calculate the voltage controller attenuator setting
amplitude = 7.5 * np.power(10, -base_atten / 20.0)
vc_atten = abs(20.0 * np.log10(
abs(voltage) / 7.5)) - base_atten - self.circuit_attenuation
if vc_atten <= self.atten.minimum_atten():
base_atten -= 1
if base_atten < 0:
logger.error(
"Voltage controlled attenuation {} under range, PSPL at Max. Decrease circuit attenuation."
.format(vc_atten))
raise ValueError(
"Voltage controlled attenuation {} under range, PSPL at Max. Decrease circuit attenuation."
.format(vc_atten))
set_voltage(voltage, base_atten=base_atten)
return
if self.atten.maximum_atten() < vc_atten:
base_atten += 1
if base_atten > 80:
logger.error(
"Voltage controlled attenuation {} over range, PSPL at Min. Increase circuit attenuation."
.format(vc_atten))
raise ValueError(
"Voltage controlled attenuation {} over range, PSPL at Min. Increase circuit attenuation."
.format(vc_atten))
set_voltage(voltage, base_atten=base_atten)
return
#print("PSPL Amplitude: {}, Attenuator: {}".format(amplitude,vc_atten))
self.atten.set_attenuation(vc_atten)
self.pspl.amplitude = self.pulse_polarity * amplitude
time.sleep(0.04)
# Assign Methods
#self.channel_bias.assign_method(lambda i: self.arb_cb.set_high_voltage(i*self.chan_bias_ref_res))
self.pulse_duration.add_post_push_hook(lambda: time.sleep(0.1))
self.pulse_duration.assign_method(self.pspl.set_duration)
self.pulse_voltage.assign_method(set_voltage)
def init_streams(self):
# Baked in data axes
descrip = DataStreamDescriptor()
descrip.data_name = 'voltage'
descrip.add_axis(
DataAxis("sample",
range(int(self.integration_time * self.ai_clock))))
descrip.add_axis(DataAxis("attempt", range(self.attempts)))
self.voltage.set_descriptor(descrip)
async def run(self):
self.digital_output.StartTask()
self.digital_output.WaitUntilTaskDone(2 * self.attempts *
self.trig_interval)
self.digital_output.StopTask()
await asyncio.sleep(0.05)
# print("\t now ", self.nidaq.points_read)
logger.debug("Stream has filled {} of {} points".format(
self.voltage.points_taken, self.voltage.num_points()))
def shutdown_instruments(self):
try:
# self.analog_input.StopTask()
self.nidaq.StopTask()
self.nidaq.ClearTask()
self.digital_output.StopTask()
del self.nidaq
except Exception as e:
print(
"Warning: failed to stop task (this normally happens with no consequences when taking multiple samples per trigger)."
)
pass
self.arb_cb.output = False
self.pspl.output = False
for name, instr in self._instruments.items():
instr.disconnect()
class ShortProcessSwitchingExperiment(Experiment):
# Parameters and outputs
pulse_duration = FloatParameter(default=5.0e-9, unit="s")
pulse_voltage = FloatParameter(default=1, unit="V")
bias_current = FloatParameter(default=60e-6, unit="A")
field = FloatParameter(default=0.0, unit="T")
voltage_chan = OutputConnector()
#voltage_MTJ = OutputConnector()
resistance_MTJ = OutputConnector()
# Constants (set with attribute access if you want to change these!)
attempts = 1 << 4
# MTJ measurements
measure_current = 3.0e-6
# Reference resistances and attenuations
matching_ref_res = 50
chan_bias_ref_res = 1e4
pspl_base_attenuation = 10
circuit_attenuation = 0
# Min/Max NIDAQ AI Voltage
min_daq_voltage = -1
max_daq_voltage = 1
# Measurement Sequence timing, clocks in Hz times in seconds
ai_clock = 0.25e6
do_clock = 1e5
run_time = 2e-4
settle_time = 0.5*run_time
integration_time = 0.1*run_time
pspl_delay = 0.25*0.5*run_time
# Instrument resources, NIDAQ called via PyDAQmx
arb_cb = Agilent33220A("192.168.5.199") # Channel Bias
pspl = Picosecond10070A("GPIB0::24::INSTR") # Gate Pulse
atten = RFMDAttenuator("calibration/RFSA2113SB_HPD_20160901.csv") # Gate Amplitude control
lock = SR865("USB0::0xB506::0x2000::002638::INSTR") # Gate Amplitude control
keith = Keithley2400("GPIB0::25::INSTR")
mag = AMI430("192.168.5.109")
def init_instruments(self):
# Channel bias arb
self.arb_cb.output = False
self.arb_cb.load_resistance = (self.chan_bias_ref_res+self.matching_ref_res)
self.arb_cb.function = 'Pulse'
self.arb_cb.pulse_period = 0.99*self.run_time
self.arb_cb.pulse_width = self.run_time - self.settle_time
self.arb_cb.pulse_edge = 100e-9
self.arb_cb.low_voltage = 0.0
self.arb_cb.high_voltage = self.bias_current.value*(self.chan_bias_ref_res+self.matching_ref_res)
self.arb_cb.polarity = 1
self.arb_cb.burst_state = True
self.arb_cb.burst_cycles = 1
self.arb_cb.trigger_source = "External"
self.arb_cb.burst_mode = "Triggered"
self.arb_cb.output = True
# Setup the Keithley
self.keith.triad()
self.keith.conf_meas_res(res_range=1e5)
self.keith.conf_src_curr(comp_voltage=0.5, curr_range=1.0e-5)
self.keith.current = self.measure_current
# Setup the magnet
self.mag.ramp()
# Setup the NIDAQ tasks
DAQmxResetDevice("Dev1")
self.nidaq = CallbackTask(["Dev1/ai0"], asyncio.get_event_loop(), int(self.integration_time*self.ai_clock), self.attempts, [self.voltage_chan],
min_voltage=self.min_daq_voltage, max_voltage=self.max_daq_voltage, ai_clock=self.ai_clock)
self.nidaq.StartTask()
# Setup DO Triggers, P1:0 triggers AWG, P1:1 triggers PSPL and DAQ analog input
self.digital_output = Task()
data_p0 = np.zeros(int(self.do_clock*self.run_time),dtype=np.uint8)
data_p0[0]=1
data_p1 = np.zeros(int(self.do_clock*self.run_time),dtype=np.uint8)
data_p1[int(self.do_clock*(self.pspl_delay))]=1 # PSPL delay
data = np.hstack([data_p0,data_p1])
self.digital_output.CreateDOChan("/Dev1/port0/line0:1","",DAQmx_Val_ChanPerLine)
self.digital_output.CfgSampClkTiming("",self.do_clock, DAQmx_Val_Rising, DAQmx_Val_FiniteSamps, int(data.size/2)*self.attempts)
self.digital_output.WriteDigitalLines(int(self.do_clock*self.run_time),0,1,DAQmx_Val_GroupByChannel,data,None,None)
# Setup the PSPL
self.pspl.amplitude = 7.5*np.power(10, (-self.pspl_base_attenuation)/20.0)
self.pspl.trigger_source = "EXT"
self.pspl.trigger_level = 0.5
self.pspl.output = True
# Setup PSPL Attenuator Control
self.atten.set_supply_method(self.lock.set_ao2)
self.atten.set_control_method(self.lock.set_ao3)
def set_pulse_voltage(voltage, base_atten=self.pspl_base_attenuation):
# Calculate the voltage controller attenuator setting
amplitude = 7.5*np.power(10, -base_atten/20.0)
vc_atten = abs(20.0 * np.log10(abs(voltage)/7.5)) - base_atten - self.circuit_attenuation
if vc_atten <= self.atten.minimum_atten():
base_atten -= 1
if base_atten < 0:
logger.error("Voltage controlled attenuation {} under range, PSPL at Max. Decrease circuit attenuation.".format(vc_atten))
raise ValueError("Voltage controlled attenuation {} under range, PSPL at Max. Decrease circuit attenuation.".format(vc_atten))
set_pulse_voltage(voltage, base_atten=base_atten)
return
if self.atten.maximum_atten() < vc_atten:
base_atten += 1
if base_atten > 80:
logger.error("Voltage controlled attenuation {} over range, PSPL at Min. Increase circuit attenuation.".format(vc_atten))
raise ValueError("Voltage controlled attenuation {} over range, PSPL at Min. Increase circuit attenuation.".format(vc_atten))
set_pulse_voltage(voltage, base_atten=base_atten)
return
#print("PSPL Amplitude: {}, Attenuator: {}".format(amplitude,vc_atten))
self.atten.set_attenuation(vc_atten)
self.pspl.amplitude = self.arb_cb.polarity*abs(amplitude)
time.sleep(0.04)
def set_awg_current(current):
if 0 <= current:
self.arb_cb.polarity = 1
self.arb_cb.low_voltage = 0
self.arb_cb.high_voltage = current*self.chan_bias_ref_res
else :
self.arb_cb.polarity = -1
self.arb_cb.low_voltage = current*self.chan_bias_ref_res
self.arb_cb.high_voltage = 0
self.pspl.amplitude = self.arb_cb.polarity*abs(self.pspl.amplitude)
time.sleep(0.04)
# Assign Methods
self.bias_current.assign_method(set_awg_current)
self.pulse_duration.add_post_push_hook(lambda: time.sleep(0.1))
self.pulse_duration.assign_method(self.pspl.set_duration)
self.pulse_voltage.assign_method(set_pulse_voltage)
self.field.assign_method(self.mag.set_field)
def init_streams(self):
# Baked in data axes
descrip = DataStreamDescriptor()
descrip.data_name='voltage'
descrip.add_axis(DataAxis("sample", range(int(self.integration_time*self.ai_clock))))
descrip.add_axis(DataAxis("attempt", range(self.attempts)))
self.voltage_chan.set_descriptor(descrip)
# descrip = DataStreamDescriptor()
# descrip.data_name='voltage'
# descrip.add_axis(DataAxis("sample", range(int(self.integration_time*self.ai_clock))))
# descrip.add_axis(DataAxis("attempt", range(self.attempts)))
# self.voltage_MTJ.set_descriptor(descrip)
descrip = DataStreamDescriptor()
descrip.data_name='resistance'
self.resistance_MTJ.set_descriptor(descrip)
async def run(self):
self.digital_output.StartTask()
self.digital_output.WaitUntilTaskDone(2*self.attempts*self.run_time)
self.digital_output.StopTask()
await self.resistance_MTJ.push(self.keith.resistance)
await asyncio.sleep(0.05)
# print("\t now ", self.nidaq.points_read)
# logger.debug("Stream has filled {} of {} points".format(self.voltage.points_taken, self.voltage.num_points() ))
def shutdown_instruments(self):
self.keith.current = 0.0e-5
self.mag.zero()
try:
for ch in [self.nidaq, self.nidaq_MTJ]:
ch.StopTask()
ch.ClearTask()
self.digital_output.StopTask()
del ch
except Exception as e:
print("Warning: failed to stop task (this normally happens with no consequences when taking multiple samples per trigger).")
pass
self.arb_cb.output = False
self.pspl.output = False
for name, instr in self._instruments.items():
instr.disconnect()
class ShortProcessSwitchingExperimentReset(Experiment):
# Parameters and outputs
pulse_duration = FloatParameter(default=5.0e-9, unit="s")
pulse_voltage = FloatParameter(default=1, unit="V")
bias_current = FloatParameter(default=60e-6, unit="A")
field = FloatParameter(default=0.0, unit="T")
voltage = OutputConnector()
polarity = 1
attempts = 1 << 4 # How many times to try switching per set of conditions
measure_current = 10.0e-6 # MTJ sense current
reset_current = 0.5e-3 # AWG reset current (remember division)
MTJ_res = 100e3 # MTJ Resistance
# Reference resistances and attenuations
matching_ref_res = 50
chan_bias_ref_res = 1e4
reset_bias_ref_res = 5e3
pspl_base_attenuation = 10
circuit_attenuation = 0
# Reset Pulse Switching Pulse
# ___/\____
# \_______/ / \
# A B C D
# |------------------------------------->
# MEAS Begins (ignore middle) MEAS Ends
# | Integ. time| |integ time|
# Measurement Sequence timing, clocks in Hz times in seconds
ai_clock = 0.25e6
do_clock = 0.5e6
trig_interval = 200e-6 # The repetition rate for switching attempts
bias_pulse_width = 40e-6 # This is how long the bias pulse is
reset_pulse_width = 40e-6 # This is how long the reset pulse is
meas_duration = 140e-6 # This is how long the meas is
reset_trig_time = 0e-6 # (A) When we trigger the reset pulse
meas_trig_time = 50e-6 # (B) When the measurement trigger begins
switch_trig_time = 4e-6 # (C) When we trigger the reset pulse
pspl_trig_time = 4e-6 # (D) When we trigger the gate pulse
integration_time = 20e-6 # How long to measure for at the beginning and end
# Instrument resources, NIDAQ called via PyDAQmx
arb_cb = Agilent33220A("192.168.5.199") # Channel Bias
arb_reset = Agilent33220A("192.168.5.198") # Channel reset pulses
pspl = Picosecond10070A("GPIB0::24::INSTR") # Gate Pulse
atten = RFMDAttenuator("calibration/RFSA2113SB_HPD_20160901.csv") # Gate Amplitude control
lock = SR865("USB0::0xB506::0x2000::002638::INSTR") # Gate Amplitude control
keith = Keithley2400("GPIB0::25::INSTR")
mag = AMI430("192.168.5.109")
def init_instruments(self):
# Channel bias arb
self.arb_cb.output = False
self.arb_cb.load_resistance = (self.chan_bias_ref_res+self.matching_ref_res)
self.arb_cb.function = 'Pulse'
self.arb_cb.pulse_period = 0.99*self.trig_interval
self.arb_cb.pulse_width = self.bias_pulse_width
self.arb_cb.pulse_edge = 100e-9
self.arb_cb.low_voltage = 0.0
self.arb_cb.high_voltage = self.bias_current.value*(self.chan_bias_ref_res+self.matching_ref_res)
self.arb_cb.polarity = self.polarity
self.arb_cb.burst_state = True
self.arb_cb.burst_cycles = 1
self.arb_cb.trigger_source = "External"
self.arb_cb.burst_mode = "Triggered"
self.arb_cb.output = True
# MTJ reset arb
self.arb_reset.output = False
self.arb_reset.load_resistance = (self.reset_bias_ref_res+self.matching_ref_res)
self.arb_reset.function = 'Pulse'
self.arb_reset.pulse_period = 0.99*self.trig_interval
self.arb_reset.pulse_width = self.reset_pulse_width
self.arb_reset.pulse_edge = 100e-9
self.arb_reset.low_voltage = 0.0
self.arb_reset.high_voltage = self.reset_current*(self.reset_bias_ref_res+self.matching_ref_res)
self.arb_reset.polarity = -self.polarity
self.arb_reset.burst_state = True
self.arb_reset.burst_cycles = 1
self.arb_reset.trigger_source = "External"
self.arb_reset.burst_mode = "Triggered"
self.arb_reset.output = True
# Setup the Keithley
self.keith.triad()
self.keith.conf_meas_res(res_range=1e5)
self.keith.conf_src_curr(comp_voltage=0.5, curr_range=1.0e-4)
self.keith.current = self.measure_current
# Setup the magnet
self.mag.ramp()
# Setup the NIDAQ tasks
DAQmxResetDevice("Dev1")
self.nidaq = CallbackTask(["Dev1/ai2"], asyncio.get_event_loop(), int(self.meas_duration*self.ai_clock), self.attempts, [self.voltage],
trigger="/Dev1/PFI12", min_voltage=-self.MTJ_res*self.measure_current, max_voltage=self.MTJ_res*self.measure_current,
ai_clock=self.ai_clock)
self.nidaq.StartTask()
self.digital_output = Task()
do_reset = np.zeros(int(self.do_clock*self.trig_interval),dtype=np.uint8)
do_reset[int(self.do_clock*self.reset_trig_time)]=1
do_bias = np.zeros(int(self.do_clock*self.trig_interval),dtype=np.uint8)
do_bias[int(self.do_clock*self.switch_trig_time)]=1
do_pspl = np.zeros(int(self.do_clock*self.trig_interval),dtype=np.uint8)
do_pspl[int(self.do_clock*self.pspl_trig_time)]=1
do_meas = np.zeros(int(self.do_clock*self.trig_interval),dtype=np.uint8)
do_meas[int(self.do_clock*self.meas_trig_time)]=1
data = np.hstack([do_reset, do_bias, do_pspl, do_meas])
self.digital_output.CreateDOChan("/Dev1/port0/line0:3","",DAQmx_Val_ChanPerLine)
self.digital_output.CfgSampClkTiming("",self.do_clock, DAQmx_Val_Rising, DAQmx_Val_FiniteSamps, int(data.size/4)*self.attempts)
self.digital_output.WriteDigitalLines(int(self.do_clock*self.trig_interval),0,1,DAQmx_Val_GroupByChannel,data,None,None)
# Setup the PSPL
self.pspl.amplitude = 7.5*np.power(10, (-self.pspl_base_attenuation)/20.0)
self.pspl.trigger_source = "EXT"
self.pspl.trigger_level = 0.5
self.pspl.output = True
# Setup PSPL Attenuator Control
self.atten.set_supply_method(self.lock.set_ao2)
self.atten.set_control_method(self.lock.set_ao3)
def set_pulse_voltage(voltage, base_atten=self.pspl_base_attenuation):
# Calculate the voltage controller attenuator setting
amplitude = 7.5*np.power(10, -base_atten/20.0)
vc_atten = abs(20.0 * np.log10(abs(voltage)/7.5)) - base_atten - self.circuit_attenuation
if vc_atten <= self.atten.minimum_atten():
base_atten -= 1
if base_atten < 0:
logger.error("Voltage controlled attenuation {} under range, PSPL at Max. Decrease circuit attenuation.".format(vc_atten))
raise ValueError("Voltage controlled attenuation {} under range, PSPL at Max. Decrease circuit attenuation.".format(vc_atten))
set_pulse_voltage(voltage, base_atten=base_atten)
return
if self.atten.maximum_atten() < vc_atten:
base_atten += 1
if base_atten > 80:
logger.error("Voltage controlled attenuation {} over range, PSPL at Min. Increase circuit attenuation.".format(vc_atten))
raise ValueError("Voltage controlled attenuation {} over range, PSPL at Min. Increase circuit attenuation.".format(vc_atten))
set_pulse_voltage(voltage, base_atten=base_atten)
return
#print("PSPL Amplitude: {}, Attenuator: {}".format(amplitude,vc_atten))
self.atten.set_attenuation(vc_atten)
self.pspl.amplitude = self.arb_cb.polarity*abs(amplitude)
time.sleep(0.04)
def set_awg_current(current):
if 0 <= current:
self.arb_cb.polarity = 1
self.arb_cb.low_voltage = 0
self.arb_cb.high_voltage = current*self.chan_bias_ref_res
else :
self.arb_cb.polarity = -1
self.arb_cb.low_voltage = current*self.chan_bias_ref_res
self.arb_cb.high_voltage = 0
self.pspl.amplitude = self.arb_cb.polarity*abs(self.pspl.amplitude)
time.sleep(0.04)
# Assign Methods
self.bias_current.assign_method(set_awg_current)
self.pulse_duration.assign_method(self.pspl.set_duration)
self.pulse_voltage.assign_method(set_pulse_voltage)
self.field.assign_method(self.mag.set_field)
self.pulse_duration.add_post_push_hook(lambda: time.sleep(0.05))
self.pulse_voltage.add_post_push_hook(lambda: time.sleep(0.05))
self.bias_current.add_post_push_hook(lambda: time.sleep(0.05))
def init_streams(self):
descrip = DataStreamDescriptor()
descrip.data_name='voltage'
descrip.add_axis(DataAxis("sample", range(int(self.meas_duration*self.ai_clock))))
descrip.add_axis(DataAxis("attempt", range(self.attempts)))
self.voltage.set_descriptor(descrip)
async def run(self):
self.digital_output.StartTask()
self.digital_output.WaitUntilTaskDone(2*self.attempts*self.trig_interval)
self.digital_output.StopTask()
await asyncio.sleep(0.05)
def shutdown_instruments(self):
self.keith.current = 0.0e-5
self.keith.triad(down=True)
self.mag.zero()
try:
for ch in [self.nidaq, self.nidaq_MTJ]:
ch.StopTask()
ch.ClearTask()
self.digital_output.StopTask()
del ch
except Exception as e:
print("Warning: failed to stop task (this normally happens with no consequences when taking multiple samples per trigger).")
pass
self.arb_cb.output = False
self.pspl.output = False
for name, instr in self._instruments.items():
instr.disconnect()
class SwitchSearchLockinExperiment(Experiment):
voltage = OutputConnector()
sample = "CSHE2"
comment = "Search PSPL Switch Voltage"
field = FloatParameter(default=0.0, unit="T")
pulse_voltage = FloatParameter(default=0, unit="V")
pulse_duration = FloatParameter(default=5.0e-9, unit="s")
# Default values for lockin measurement. These will need to be changed in a notebook to match the MR and switching current of the sample being measured
res_reference = 1e3
sample_resistance = 50
measure_current = 10e-6
fdB = 18
tc = 100e-3
circuit_attenuation = 20.0
pspl_base_attenuation = 30.0
attempts = 1 << 8 # Number of attemps
samps_per_trig = 10 # Samples per trigger
# Instruments
arb = KeysightM8190A("192.168.5.108")
pspl = Picosecond10070A("GPIB0::24::INSTR")
mag = AMI430("192.168.5.109")
lock = SR865("USB0::0xB506::0x2000::002638::INSTR")
atten = RFMDAttenuator("calibration/RFSA2113SB_HPD_20160901.csv")
min_daq_voltage = 0
max_daq_voltage = 10
def init_instruments(self):
# ===================
# Setup the Lockin
# ===================
self.lock.tc = self.tc
self.lock.filter_slope = self.fdB
self.lock.amp = (self.res_reference +
self.sample_resistance) * self.measure_current
sense_vals = np.array(self.lock.SENSITIVITY_VALUES)
self.lock.sensitivity = sense_vals[np.argmin(
np.absolute(sense_vals - 2 * self.sample_resistance *
self.measure_current * np.ones(sense_vals.size)))]
time.sleep(20 * self.lock.measure_delay())
# Rescale lockin analogue output for NIDAQ
self.lock.r_offset_enable = True
self.lock.r_expand = 100
self.lock.auto_offset("R")
self.lock.r_offset = 0.99 * self.lock.r_offset
#self.lock.r_offset = 100 * ((self.sample_resistance*self.measure_current/self.lock.sensitivity) - (0.05/self.lock.r_expand))
time.sleep(20 * self.lock.measure_delay())
# Ramp magnet to set point
self.mag.ramp()
#Set attenuator control methods
self.atten.set_supply_method(self.lock.set_ao2)
self.atten.set_control_method(self.lock.set_ao3)
# ===================
# Setup the AWG
# ===================
self.arb.set_output(True, channel=1)
self.arb.set_output(False, channel=2)
self.arb.sample_freq = 12.0e9
self.arb.waveform_output_mode = "WSPEED"
self.arb.set_output_route("DC", channel=1)
self.arb.voltage_amplitude = 1.0
self.arb.set_marker_level_low(0.0, channel=1, marker_type="sync")
self.arb.set_marker_level_high(1.5, channel=1, marker_type="sync")
self.arb.continuous_mode = False
self.arb.gate_mode = False
# ===================
# Setup the PSPL
# ===================
# PSPL Max amplitude is 7.5 V
self.pspl.amplitude = 7.5 * np.power(
10, -self.pspl_base_attenuation / 20.0)
self.pspl.trigger_source = "EXT"
self.pspl.trigger_level = 0.1
self.pspl.output = True
self.setup_daq()
def set_voltage(voltage):
# Calculate the voltage controller attenuator setting
self.pspl.amplitude = np.sign(voltage) * 7.5 * np.power(
10, -self.pspl_base_attenuation / 20.0)
vc_atten = abs(
20.0 * np.log10(abs(voltage) / 7.5)
) - self.pspl_base_attenuation - self.circuit_attenuation
if vc_atten <= self.atten.minimum_atten():
logger.error(
"Voltage controlled attenuation {} under range.".format(
vc_atten))
raise ValueError(
"Voltage controlled attenuation {} under range.".format(
vc_atten))
if self.atten.maximum_atten() < vc_atten:
logger.error(
"Voltage controlled attenuation {} over range.".format(
vc_atten))
raise ValueError(
"Voltage controlled attenuation {} over range.".format(
vc_atten))
self.atten.set_attenuation(vc_atten)
time.sleep(0.02)
# Assign methods
self.field.assign_method(self.mag.set_field)
self.pulse_duration.assign_method(self.pspl.set_duration)
self.pulse_voltage.assign_method(set_voltage)
# Create hooks for relevant delays
self.pulse_duration.add_post_push_hook(lambda: time.sleep(0.1))
def setup_daq(self):
self.arb.abort()
self.arb.delete_all_waveforms()
self.arb.reset_sequence_table()
# Picosecond trigger waveform
pspl_trig_wf = KeysightM8190A.create_binary_wf_data(np.zeros(3200),
samp_mkr=1)
pspl_trig_segment_id = self.arb.define_waveform(len(pspl_trig_wf))
self.arb.upload_waveform(pspl_trig_wf, pspl_trig_segment_id)
# NIDAQ trigger waveform
nidaq_trig_wf = KeysightM8190A.create_binary_wf_data(np.zeros(3200),
sync_mkr=1)
nidaq_trig_segment_id = self.arb.define_waveform(len(nidaq_trig_wf))
self.arb.upload_waveform(nidaq_trig_wf, nidaq_trig_segment_id)
settle_pts = int(640 * np.ceil(self.lock.measure_delay() * 12e9 / 640))
scenario = Scenario()
seq = Sequence(sequence_loop_ct=int(self.attempts))
seq.add_waveform(pspl_trig_segment_id)
seq.add_idle(settle_pts, 0.0)
seq.add_waveform(nidaq_trig_segment_id)
seq.add_idle(1 << 16, 0.0) # bonus non-contiguous memory delay
scenario.sequences.append(seq)
self.arb.upload_scenario(scenario, start_idx=0)
self.arb.sequence_mode = "SCENARIO"
self.arb.scenario_advance_mode = "REPEAT"
self.arb.scenario_start_index = 0
self.arb.run()
# ===================
# Setup the NIDAQ
# ===================
self.analog_input = Task()
self.read = int32()
self.buf_points = self.samps_per_trig * self.attempts
self.analog_input.CreateAIVoltageChan("Dev1/ai0", "", DAQmx_Val_Diff,
self.min_daq_voltage,
self.max_daq_voltage,
DAQmx_Val_Volts, None)
self.analog_input.CfgSampClkTiming("", 1e6, DAQmx_Val_Rising,
DAQmx_Val_FiniteSamps,
self.samps_per_trig)
self.analog_input.CfgInputBuffer(self.buf_points)
self.analog_input.CfgDigEdgeStartTrig("/Dev1/PFI0", DAQmx_Val_Rising)
self.analog_input.SetStartTrigRetriggerable(1)
self.analog_input.StartTask()
def init_streams(self):
# Baked in data axes
descrip = DataStreamDescriptor()
descrip.add_axis(DataAxis("sample", range(self.samps_per_trig)))
descrip.add_axis(DataAxis("attempts", range(self.attempts)))
self.voltage.set_descriptor(descrip)
async def run(self):
self.arb.advance()
self.arb.trigger()
buf = np.empty(self.buf_points)
self.analog_input.ReadAnalogF64(self.buf_points, -1,
DAQmx_Val_GroupByChannel, buf,
self.buf_points, byref(self.read),
None)
logger.debug("Read a buffer of {} points".format(buf.size))
await self.voltage.push(buf)
# Seemingly we need to give the filters some time to catch up here...
await asyncio.sleep(0.02)
logger.debug("Stream has filled {} of {} points".format(
self.voltage.points_taken, self.voltage.num_points()))
def shutdown_instruments(self):
try:
self.analog_input.StopTask()
except Exception as e:
logger.warning(
"Warning failed to stop task, which is quite typical (!)")
self.arb.stop()
self.pspl.output = False
self.lock.amp = 0