Example template

At this point, you have everything you need to run measurements with qcodes++. An example Jupyter notebook for running realistic measurements is included with the installation, and is also available for download here.

How to download from github — Click on the download icon in the top right corner..

The code

# Optional: check for VISA instruments

import qcodespp as qc
qc.listVISAinstruments()

# Import packages, instrument drivers, and connect to instruments.

import qcodespp as qc
import numpy as np
import time

from qcodespp.instrument_drivers.QDevil.QDAC2 import QDac2
from qcodespp.instrument_drivers.ZI.ZIHF2LI import ZIHF2LI
from qcodespp.instrument_drivers.tektronix.Keithley_2450 import Keithley_2450

qdac = QDac2('qdac','ASRL9::INSTR')
li = ZIHF2LI('li','dev1832') # ZI instruments don't use VISA
k2450 = Keithley_2450('k2450','TCPIP0::169.254.100.202::inst0::INSTR')

# Define custom parameters

stepper=qc.Parameter('stepper',label='Stepper',unit='',set_cmd=lambda val: 0)

currentX=qc.ScaledParameter(li.demod0_X,gain=1e-6,name='currentX',label='Current',unit='A')
currentY=qc.ScaledParameter(li.demod0_Y,gain=1e-6,name='currentY',label='Current',unit='A')
voltageX=qc.ScaledParameter(li.demod1_X,gain=1e-3,name='voltageX',label='Voltage',unit='V')
voltageY=qc.ScaledParameter(li.demod1_Y,gain=1e-3,name='voltageY',label='Voltage',unit='V')

resistance=qc.Parameter('resistance',label='Resistance',unit='Ohm',get_cmd=lambda: voltageX()/currentX())

# Tell qcodespp where to store data
qc.set_data_folder('data')

# Init the station.
station=qc.Station(add_variables=globals())

# 1D loops
loop=qc.loop1d(sweep_parameter=qdac.ch01.volt,
           start=0,stop=1,num=101,delay=0.03,
           device_info='Device1',
           instrument_info=f'ACdiv=1e5 DCdiv=1e3 freq={li.osc0_freq():.6g} Hz',
           measure=[currentX, currentY, voltageX, voltageY, resistance],
           plot=[currentX,voltageX,resistance])

data = loop.run()

# 1D loop with a break condition
loop=qc.loop1d(sweep_parameter=k2450.volt,
            start=0,stop=1,num=101,delay=0.03,
            device_info='Device1',
            instrument_info=f'ACdiv=1e5 DCdiv=1e3 freq={li.osc0_freq():.6g} Hz',
            measure=[qc.BreakIf(lambda: np.abs(k2450.curr())>1e-9),
                        currentX, currentY, voltageX, voltageY, resistance],
            plot=[currentX,voltageX,resistance])

data = loop.run()

# 2D loop
loop=qc.loop2d(sweep_parameter=qdac.ch01.volt,
                start=0,stop=1,num=11,delay=0.03,
                step_parameter=k2450.volt,
                step_start=0,step_stop=1,step_num=11,step_delay=0.1,
                device_info='Device1',
                instrument_info=f'ACdiv=1e5 DCdiv=1e3 freq={li.osc0_freq():.6g} Hz',
                measure=[currentX, currentY, voltageX, voltageY, resistance],
                plot=[currentX,voltageX,resistance])

data = loop.run()

# 2D loops with sweep in both directions.
loop=qc.loop2dUD(sweep_parameter=qdac.ch01.volt,
                start=0,stop=1,num=11,delay=0.03,
                step_parameter=k2450.volt,
                step_start=0,step_stop=1,step_num=11,step_delay=0.1,
                device_info='Device1',
                instrument_info=f'ACdiv=1e5 DCdiv=1e3 freq={li.osc0_freq():.6g} Hz',
                measure=[currentX, currentY, voltageX, voltageY, resistance],
                plot=[currentX,voltageX,resistance])

data = loop.run()