def sweep(freqs, sens_bands, save_path):
# Initialize instruments
ew.initialize()
# Set the frequency multiplier, as it is particular to the experiment
ew.set_freq_multiplier(18)
# Setup the frequency synthesizer
ew.set_freq_synth_power(15.0)
ew.set_freq_synth_enable(True)
# Setup chopper
ew.set_chopper_amplitude(5.0)
ew.set_chopper_frequency(0.010) # 10Hz chop frequency
ew.set_chopper_on(True)
# Setup lock-in
ew.set_time_constant(300.0)
ew.set_low_pass_slope(24.0)
ew.set_sync_enabled(True)
# Sleep to allow instruments to adjust settings
time.sleep(4.0)
# Create a new array to save data to
data = np.array([0, 0, 0], float) # This row will be deleted later
# Sweep the selected parameter and record data
for freq in freqs:
print('At frequency ' + str(freq) + 'GHz')
# Set sensitivity and frequency
ew.set_sensitivity(get_sensitivity_setting(freq, sens_bands))
time.sleep(0.3) # Allow sensitivity to set
ew.set_freq_synth_frequency(freq)
# Sleep to allow lock-in to lock to new frequency and for time constant to average
time.sleep(
300.0 * 5.0 / 1000.0 + 0.5
) # Sleep for five time constants plus an additional half a second
# Get data from the lock-in amplifier and and add it to the data array
(x, y) = ew.snap_data()
data_row = np.array([freq, x, y])
data = np.vstack((data, data_row))
# Delete the first row in the collected data, as it was created to give the array shape earlier but holds no useful data
data = np.delete(data, 0, 0)
np.save(save_path, data)
import numpy as np
import time
from setup_control import experiment_wrapper as ew
# Initialize setup
ew.initialize()
# Set the frequency multiplier, as it is particular to the experiment
ew.set_freq_multiplier(18)
# Setup the frequency synthesizer
ew.set_freq_synth_power(15.0)
ew.set_freq_synth_enable(True)
# Setup chopper
ew.set_chopper_amplitude(5.0)
ew.set_chopper_frequency(1.0)
ew.set_chopper_on(True)
# Setup lock-in
ew.set_time_constant(100.0)
ew.set_low_pass_slope(24.0)
# Sleep to allow instruments to adjust settings
time.sleep(4.0)
# Frequencies to test, along with the appropriate sensitivities
freqs_sens = [(225.0, 0.005), (230.0, 0.005), (235.0, 0.002), (240.0, 0.005),
(245.0, 0.005), (250.0, 0.002), (255.0, 0.002), (260.0, 0.005),
(265.0, 0.002), (270.0, 0.002), (275.0, 0.002)]
"""
Sweeps from 12.5GHz to 16.5GHz in 25MHz steps. Power of the frequency synthesizer is set to 8dBm in an attempt to get out of the diode's saturation range. Returns values in volts.
"""
for i in range(0, 3):
experiment_wrapper.initialize()
# Disable chopper
experiment_wrapper.set_chopper_on(False)
# Set the frequency multiplier, as it is particular to the experiment
experiment_wrapper.set_freq_multiplier(1)
# Setup the frequency synthesizer
experiment_wrapper.set_freq_synth_power(8.0)
experiment_wrapper.set_freq_synth_enable(True)
# Sleep to allow instruments to adjust settings
time.sleep(5)
# Create a new array to save data to
data = np.array([0, 0], float) # This row will be deleted later
# Sweep the selected parameter and record data
for freq in np.linspace(12.5, 16.5, num=160, endpoint=True):
print('At frequency ' + str(freq))
# Set selected parameter to the given value
experiment_wrapper.set_freq_synth_frequency(freq)
# Sleep to allow multimeter to reset and then clear buffer