def sweep_current_flux(app, curves, current_point, card1, card2, channel1,
channel2, I_min, I_max, step, I_minflux, I_maxflux,
stepflux, down):
"""
Inputs are min and max current for sweep, steps, card and channels for switch
Returns an array with current steps, measured voltages, and calculated resistances
"""
curve_colors = ['b', 'g', 'r', 'c', 'm', 'y', 'k', 'w']
I_values_all = [] #(Ibias)
V_values_all = []
current_x = []
current_y = []
##INITIALIZATION OF HARDWARE##
Voltmeter = vf.get_voltage()
CurrentSource = vf.get_current()
FluxSource = vf.get_current_flux()
Switch = vf.get_switch()
vf.intialize_switch_all(Switch)
vf.intialize_current_yoko(CurrentSource, Irange, compliance_voltage)
time.sleep(0.2)
vf.intialize_current_yoko(FluxSource, Fluxrange, compliance_voltage)
time.sleep(0.2)
vf.intialize_voltage(Voltmeter, nplc, Vrange)
vf.close_channel(Switch, card1, channel1)
time.sleep(0.2)
vf.close_channel(Switch, card2, channel2) # instead of card, used to be 1
time.sleep(0.2)
vf.turnon_current_yoko(CurrentSource)
time.sleep(0.2)
vf.turnon_current_yoko(FluxSource)
time.sleep(0.2)
vf.open_short(Switch, card1, shorts)
time.sleep(0.2)
time.sleep(0.2)
curve_counter = 0
global go
go = 1
colorsused = []
for Iflux in np.arange(I_minflux, I_maxflux, stepflux):
I_values = []
V_values = []
vf.set_current_fast_yoko(FluxSource, Iflux) #Set the flux current
#vf.intialize_voltage(Voltmeter, nplc, Vrange)
offset = vf.read_voltage_fast(Voltmeter, VDwellTime)
time.sleep(0.2)
##CURRENT SWEEPS##
#Sweep Current up
print('Starting sweep up with Iflux =', Iflux)
for I in np.arange(I_min, I_max, step):
vf.set_current_fast_yoko(CurrentSource, I)
V = vf.read_voltage_fast(Voltmeter, VDwellTime)
I_values.append(I)
V_values.append(V)
current_x.append(I)
current_y.append(V)
curves[curve_counter].setData(
I_values,
V_values,
symbol='o',
symbolBrush=curve_colors[curve_counter % 8],
symbolSize=5)
current_point.setData(current_x,
current_y,
symbol='o',
symbolBrush='r',
symbolSize=7)
app.processEvents()
current_x = []
current_y = []
if go == 0: #If the stop button on the GUI is pressed
exitfunc(Switch, CurrentSource, card1, card2, channel1,
channel2)
vf.set_current_fast_yoko(FluxSource, 0)
return 0, 0, 0
if down:
print('Starting sweep down')
#Sweep Current down
for I in np.arange(I_max - step, I_min, -step):
vf.set_current_fast_yoko(CurrentSource, I)
V = vf.read_voltage_fast(Voltmeter, VDwellTime)
I_values.append(I)
V_values.append(V)
current_x.append(I)
current_y.append(V)
curves[curve_counter].setData(
I_values,
V_values,
symbol='o',
symbolBrush=curve_colors[curve_counter % 8],
symbolSize=5)
current_point.setData(current_x,
current_y,
symbol='o',
symbolBrush='r',
symbolSize=7)
app.processEvents()
current_x = []
current_y = []
if go == 0: #If the stop button on the GUI is pressed
exitfunc(Switch, CurrentSource, card1, card2, channel1,
channel2)
vf.set_current_fast_yoko(FluxSource, 0)
return 0, 0, 0
V_values = np.array(V_values)
V_values = V_values - offset
#SHUT IT DOWN!##
print('Exited current sweep with Iflux =', Iflux)
vf.set_current_fast_yoko(CurrentSource, 0)
time.sleep(.1)
I_values_all.append(I_values)
V_values_all.append(V_values)
colorsused.append(curve_colors[curve_counter % 8])
curve_counter = curve_counter + 1
print('Finished all current sweeps')
#Safe all of the hardware
vf.set_current_fast_yoko(FluxSource, 0)
time.sleep(0.2)
vf.close_short(Switch, card1, shorts)
time.sleep(0.2)
if channel1 != 10:
vf.open_channel(Switch, card1, channel1)
vf.open_channel(Switch, card2, channel2)
#Iflux=np.arange(I_minflux, I_maxflux, stepflux)
return I_values_all, V_values_all, colorsused
def sweep_current_vphi(app, curve, current_point, card1, card2, channel1,
channel2, I_minflux, I_maxflux, Iflux_step, Ibias_min,
Ibias_max, Ibias_step):
"""
Inputs are min and max current for sweep for flux of the SQUIDs, step
Returns an array with current steps, measured voltages, and calculated resistances
*********NOTE: This will have to be modified if the second current source is wired through the switch matrix
"""
##VARIABLE DECLARATIONS##
#Going to use lists to start with for flexibility, even though slower than arrays
I_values = []
V_values = []
current_x = []
current_y = []
##INITIALIZATION OF HARDWARE##
Voltmeter = vf.get_voltage()
CurrentSource = vf.get_current()
FluxSource = vf.get_current_flux()
Switch = vf.get_switch()
vf.intialize_switch_all(Switch)
vf.intialize_current_yoko(
CurrentSource, Irange, compliance_voltage
) #50 mA instead of 10 mA because we want a larger range for periodicity tests
time.sleep(0.2)
vf.intialize_current_yoko(FluxSource, 50e-03, compliance_voltage)
time.sleep(0.2)
vf.intialize_voltage(Voltmeter, nplc, Vrange)
vf.close_channel(Switch, card1, channel1)
time.sleep(0.2)
vf.close_channel(Switch, card2, channel2) # instead of card, used to be 1
time.sleep(0.2)
vf.turnon_current_yoko(CurrentSource)
time.sleep(0.2)
vf.turnon_current_yoko(FluxSource)
time.sleep(0.2)
vf.open_short(Switch, card1, shorts)
time.sleep(0.2)
offset = vf.read_voltage_fast(Voltmeter, VDwellTime)
global go
go = 1
for Ibias in np.arange(Ibias_min, Ibias_max, Ibias_step):
vf.set_current_fast_yoko(CurrentSource, Ibias)
I = []
V = []
##CURRENT SWEEPS##
#Sweep Current up
print('Starting sweep with Ibias = %f' % Ibias)
for Iflux in np.arange(I_minflux, I_maxflux, Iflux_step):
vf.set_current_fast_yoko(FluxSource, Iflux)
Vread = vf.read_voltage_fast(Voltmeter, VDwellTime)
I.append(Iflux)
V.append(Vread)
current_x.append(Iflux)
current_y.append(Vread)
curve.setData(I, V, symbol='o', symbolBrush='w', symbolSize=5)
current_point.setData(current_x,
current_y,
symbol='o',
symbolBrush='r',
symbolSize=7)
app.processEvents()
current_x = []
current_y = []
if go == 0: #If the stop button on the GUI is pressed
exitfunc(Switch, CurrentSource, card1, card2, channel1,
channel2)
vf.set_current_fast_yoko(FluxSource, 0)
return 0, 0, 0
vf.set_current_fast_yoko(CurrentSource, 0)
vf.set_current_fast_yoko(FluxSource, 0)
I = np.array(I)
V = np.array(V)
I_values.append(I)
V_values.append(V - offset)
if go == 0: #If the stop button on the GUI is pressed
exitfunc(Switch, CurrentSource, card1, card2, channel1, channel2)
vf.set_current_fast_yoko(FluxSource, 0)
return 0, 0, 0
print("Exited current sweep")
vf.set_current_fast_yoko(CurrentSource, 0)
time.sleep(.2)
vf.set_current_fast_yoko(FluxSource, 0)
time.sleep(.2)
vf.close_short(Switch, card1, shorts)
time.sleep(0.2)
if channel1 != 10:
vf.open_channel(Switch, card1, channel1)
vf.open_channel(Switch, card2, channel2)
x = I
y = np.full(np.shape(I), np.mean(V))
current_point.setData(x, y, symbol='o', symbolBrush='g', symbolSize=7)
return find_period(I_values, V_values)