M91 Fast Hall Controller

The Lake Shore M91 Fast Hall controller makes high speed Hall measurements for materials characterization.

More information about the instrument can be found on our website including the manual which has a list of all SCPI commands and queries.

Example Scripts

Below are a few example scripts for the M91 Fast Hall Controller that use the Lake Shore Python driver.

Fast Hall Full Sample Analysis

from lakeshore import FastHall
from lakeshore import ContactCheckOptimizedParameters, ResistivityLinkParameters, FastHallLinkParameters

# Connect to the first available FastHall over USB
my_fast_hall = FastHall()

# Create an optimized contact check settings object that limits the max current to 1 mA
ccheck_settings = ContactCheckOptimizedParameters(max_current=1e-3)

# Define the DC magnetic field strength of the measurement
magnetic_field_strength = 0.1

# Create a resistivity and FastHall measurement linked settings objects
resistivity_settings = ResistivityLinkParameters()
fasthall_settings = FastHallLinkParameters(magnetic_field_strength)

# Run the optimized contact check to automatically determine the best parameters for the sample
ccheck_results = my_fast_hall.run_complete_contact_check_optimized(ccheck_settings)

# Run a resistivity measurement linking the parameters determined by the contact check
resistivity_results = my_fast_hall.run_complete_resistivity_link(resistivity_settings)

# Prompt the user to insert the sample into the defined field
input("Insert sample into " + str(magnetic_field_strength) + " Tesla field")

# Run the FastHall measurement linking information from the resistivity and contact check measurements
fasthall_results = my_fast_hall.run_complete_fasthall_link(fasthall_settings)

# Dump the data into a text file
results_file = open("sample_analysis.txt", "w")
results_file.write("Contact check results:\n" + str(ccheck_results))
results_file.write("\nResistivity results:\n" + str(resistivity_results))
results_file.write("\nFastHall results:\n" + str(fasthall_results))

Fast Hall Record Contact Check Data

from lakeshore import FastHall, ContactCheckManualParameters

# Connect to the first available FastHall over USB
my_fast_hall = FastHall()

# Create a contact check parameters object with desired settings to run a manual Contact Check measurement
ccheck_settings = ContactCheckManualParameters(excitation_type='CURRENT',
                                               excitation_start_value=-10e-6,
                                               excitation_end_value=10e-6,
                                               compliance_limit=1.5,
                                               number_of_points=20)
# Create a file to write data into
file = open("fasthall_data.csv", "w")

# Write header info including the type of test and specific measurements being taken
file.write('Contact Check of Van der Pauw Sample with Varying Current Excitation Ranges\n')
file.write('Contact Pair 1-2\n')
file.write(' , Offset, Slope, R Squared, R Squared Passed, In Compliance, Voltage Overload, Current Overload\n')

# Create a list of current excitation ranges
excitation_ranges = [10e-3, 10e-4, 10e-5, 10e-6]

# Run a separate Contact Check measurement and collect results for each range in the list of excitation ranges
for range_value in excitation_ranges:

    # Set the value of the excitation range
    ccheck_settings.excitation_range = range_value

    # Write the specific excitation range that is being used
    file.write('Excitation Range: ' + str(range_value) + 'A\n')

    # Run a complete contact check measurement using the settings with the updated excitation range
    results = my_fast_hall.run_complete_contact_check_manual(ccheck_settings, sample_type="VDP")

    # Collect the measurement results that correlate to the first contact pair (Contact Pair 1-2)
    contact_pair_results = results.get('ContactPairIVResults')
    pair_one_results = contact_pair_results[0]

    # Obtain contact pair result values, then convert them into a list and then a string
    logged_keys = ['Offset', 'Slope', 'RSquared', 'RSquaredPass', 'InCompliance', 'VoltageOverload', 'CurrentOverload']
    logged_values = [pair_one_results[key] for key in logged_keys]
    logged_string = ','.join(str(value) for value in logged_values)

    # Write the result values to the file
    file.write(',' + logged_string + '\n')

# Close the file so that it can be used by the function
file.close()

Instrument class methods

class lakeshore.fast_hall_controller.FastHall(serial_number=None, com_port=None, baud_rate=921600, flow_control=True, timeout=2.0, ip_address=None, tcp_port=7777, **kwargs)

A class object representing a Lake Shore M91 Fast Hall controller

get_contact_check_running_status()

Indicates if the contact check measurement is running.

get_fasthall_running_status()

Indicates if the FastHall measurement is running

get_four_wire_running_status()

Indicates if the four wire measurement is running

get_resistivity_running_status()

Indicates if the resistivity measurement is running

get_dc_hall_running_status()

Indicates if the DC Hall measurement is running

get_dc_hall_waiting_status()

Indicates if the DC hall measurement is running.

continue_dc_hall()

Continues the DC hall measurement if it’s in a waiting state

start_contact_check_vdp_optimized(settings)

Automatically determines excitation value and ranges. Then runs contact check on all 4 pairs.

Args:
settings(ContactCheckOptimizedParameters):
start_contact_check_vdp(settings)

Performs a contact check measurement on contact pairs 1-2, 2-3, 3-4, and 4-1.

Args:
settings(ContactCheckManualParameters):
start_contact_check_hbar(settings)

Performs a contact check measurement on contact pairs 5-6, 5-1, 5-2, 5-3, 5-4, and 6-1

Args:
settings(ContactCheckManualParameters):
start_fasthall_vdp(settings)

Performs a FastHall measurement.

Args:
settings (FastHallManualParameters):

Performs a FastHall (measurement that uses the last run contact check measurement’s excitation type, compliance limit, blanking time, excitation range, and the largest absolute value of the start and end excitation values along with the last run resistivity measurement’s resistivity average and sample thickness.

Args:
settings (FastHallLinkParameters)
start_four_wire(settings)

Performs a Four wire measurement. Excitation is sourced from Contact Point 1 to Contact Point 2. Voltage is measured/sensed between contact point 3 and contact point 4.

Args:
settings(FourWireParameters)
start_dc_hall_vdp(settings)

Performs a DC hall measurement for a Hall Bar sample.

Args:
settings(DCHallParameters)
start_dc_hall_hbar(settings)

Performs a DC hall measurement for a Hall Bar sample.

Args:
settings(DCHallParameters)
start_resistivity_vdp(settings)

Performs a resistivity measurement on a Van der Pauw sample.

Args:
settings(ResistivityManualParameters)

Performs a resistivity measurement that uses the last run contact check measurement’s excitation type, compliance limit, blanking time, excitation range, and the largest absolute value of the start and end excitation values.

Args:
settings(ResistivityLinkParameters)
start_resistivity_hbar(settings)

Performs a resistivity measurement on a hall bar sample.

Args:
settings(ResistivityManualParameters)
get_contact_check_setup_results()

Returns an object representing the setup results of the last run Contact Check measurement

get_contact_check_measurement_results()

Returns a dictionary representing the results of the last run Contact Check measurement

get_fasthall_setup_results()

Returns an object representing the setup results of the last run FastHall measurement

get_fasthall_measurement_results()

Returns a dictionary representing the results of the last run FastHall measurement

get_four_wire_setup_results()

Returns an object representing the setup results of the last run Four Wire measurement

get_four_wire_measurement_results()

Returns a dictionary representing the results of the last run Four Wire measurement

get_dc_hall_setup_results()

Returns a dictionary representing the setup results of the last run Hall measurement

get_dc_hall_measurement_results()

Returns a dictionary representing the results of the last run Hall measurement

get_resistivity_setup_results()

Returns an object representing the setup results of the last run Resistivity measurement

get_resistivity_measurement_results()

Returns a dictionary representing the results of the last run Resistivity measurement

run_complete_contact_check_optimized(settings)

Performs a contact check measurement and then returns the corresponding measurement results.

Args:
settings(ContactCheckOptimizedParameters)
Returns:
The measurement results as a dictionary.
run_complete_contact_check_manual(settings, sample_type)

Performs a manual contact check measurement and then returns the corresponding measurement results.

Args:

settings(ContactCheckManualParameters)

sample_type(str):
  • Indicates sample type. Options are:
  • “VDP” (Van der Pauw sample)
  • “HBAR” (Hall Bar sample)
Returns:
The measurement results as a dictionary.

Performs a FastHall Link measurement and then returns the corresponding measurement results.

Args:
settings(FastHallLinkParameters)
Returns:
The measurement results as a dictionary.
run_complete_fasthall_manual(settings)

Performs a manual FastHall measurement and then returns the corresponding measurement results.

Args:
settings(FastHallManualParameters)
Returns:
The measurement results as a dictionary.
run_complete_four_wire(settings)

Performs a Four Wire measurement and then returns the corresponding measurement results.

Args:
settings(FourWireParameters)
Returns:
The measurement results as a dictionary.
run_complete_dc_hall(settings, sample_type)

Performs a DC Hall measurement and then returns the corresponding measurement results.

Args:

settings(DCHallParameters)

sample_type(str):
  • Indicates sample type. Options are:
  • “VDP” (Van der Pauw sample)
  • “HBAR” (Hall Bar sample)
Returns:
The measurement results as a dictionary.

Performs a resistivity link measurement and then returns the corresponding measurement results.

Args:
settings(ResistivityLinkParameters)
Returns:
The measurement results as a dictionary.
run_complete_resistivity_manual(settings, sample_type)

Performs a manual resistivity measurement and then returns the corresponding measurement results.

Args:

settings(ResistivityManualParameters)

sample_type(str):
  • Indicates sample type. Options are:
  • “VDP” (Van der Pauw sample)
  • “HBAR” (Hall Bar sample)
Returns:
The measurement results as a dictionary.
reset_contact_check_measurement()

Resets the measurement to a not run state, canceling any running measurement

reset_fasthall_measurement()

Resets the measurement to a not run state, canceling any running measurement

reset_four_wire_measurement()

Resets the measurement to a not run state, canceling any running measurement

reset_dc_hall_measurement()

Resets the measurement to a not run state, canceling any running measurement

reset_resistivity_measurement()

Resets the measurement to a not run state, canceling any running measurement

command(*commands, check_errors=True)

Send a SCPI command or multiple commands to the instrument

Args:
commands (str):
Any number of SCPI commands.
Kwargs:
check_errors (bool):
Chooses whether to query the SCPI error queue and raise errors as exceptions. True by default.
connect_tcp(ip_address, tcp_port, timeout)

Establishes a TCP connection with the instrument on the specified IP address

connect_usb(serial_number=None, com_port=None, baud_rate=None, data_bits=None, stop_bits=None, parity=None, timeout=None, handshaking=None, flow_control=None)

Establish a serial USB connection

disconnect_tcp()

Disconnect the TCP connection

disconnect_usb()

Disconnect the USB connection

factory_reset()

Resets all system information such as settings, wi-fi connections, date and time, etc.

get_operation_event_enable_mask()

Returns the names of the operation event enable register bits and their values. These values determine which operation bits propagate to the operation event register.

get_operation_events()

Returns the names of operation event status register bits that are currently high. The event register is latching and values are reset when queried.

get_present_operation_status()

Returns the names of the operation status register bits and their values

get_present_questionable_status()

Returns the names of the questionable status register bits and their values

get_questionable_event_enable_mask()

Returns the names of the questionable event enable register bits and their values. These values determine which questionable bits propagate to the questionable event register.

get_questionable_events()

Returns the names of questionable event status register bits that are currently high. The event register is latching and values are reset when queried.

get_service_request_enable_mask()

Returns the named bits of the status byte service request enable register. This register determines which bits propagate to the master summary status bit

get_standard_event_enable_mask()

Returns the names of the standard event enable register bits and their values. These values determine which bits propagate to the standard event register

get_standard_events()

Returns the names of the standard event register bits and their values

get_status_byte()

Returns named bits of the status byte register and their values

modify_operation_register_mask(bit_name, value)

Gets the operation condition register mask, changes a bit, and sets the register

Args:
bit_name (str):
The name of the bit to modify.
value (bool):
Determines whether the bit masks (false) or passes (true) the corresponding state.
modify_questionable_register_mask(bit_name, value)

Gets the questionable condition register mask, changes a bit, and sets the register

Args:
bit_name (str):
The name of the bit to modify.
value (bool):
Determines whether the bit masks (false) or passes (true) the corresponding state.
modify_service_request_mask(bit_name, value)

Gets the service request enable mask, changes a bit, and sets the register.

Args:
bit_name (str):
The name of the bit to modify.
value (bool):
Determines whether the bit masks (false) or passes (true) the corresponding state.
modify_standard_event_register_mask(bit_name, value)

Gets the standard event register mask, changes a bit, and sets the register

Args:
bit_name (str):
The name of the bit to modify.
value (bool):
Determines whether the bit masks (false) or passes (true) the corresponding state.
query(*queries, check_errors=True)

Send a SCPI query or multiple queries to the instrument and return the response(s)

Args:
queries (str):
Any number of SCPI queries or commands.
Kwargs:
check_errors (bool):
Chooses whether to query the SCPI error queue and raise errors as exceptions. True by default.
Returns:
The instrument query response as a string.
reset_measurement_settings()

Resets measurement settings to their default values.

reset_status_register_masks()

Resets status register masks to preset values

set_operation_event_enable_mask(register_mask)

Configures the values of the operation event enable register bits. These values determine which operation bits propagate to the operation event register.

Args:
register_mask ([Instrument]OperationRegister):
An instrument specific OperationRegister class object with all bits configured true or false.
set_questionable_event_enable_mask(register_mask)

Configures the values of the questionable event enable register bits. These values determine which questionable bits propagate to the questionable event register.

Args:
register_mask ([Instrument]QuestionableRegister):
An instrument specific QuestionableRegister class object with all bits configured true or false.
set_service_request_enable_mask(register_mask)

Configures values of the service request enable register bits. This register determines which bits propagate to the master summary bit

Args:
register_mask (StatusByteRegister):
A StatusByteRegister class object with all bits configured true or false.
set_standard_event_enable_mask(register_mask)

Configures values of the standard event enable register bits. These values determine which bits propagate to the standard event register

Args:
register_mask (StandardEventRegister):
A StandardEventRegister class object with all bits configured true or false.

Settings classes

This page outlines the classes and objects used to interact with various settings and methods of the M91.

class lakeshore.fast_hall_controller.FastHallOperationRegister(settling, ranging, measurement_complete, waiting_for_trigger, field_control_ramping, field_measurement_enabled, transient)

Class object representing the operation status register

class lakeshore.fast_hall_controller.FastHallQuestionableRegister(source_in_compliance_or_at_current_limit, field_control_slew_rate_limit, field_control_at_voltage_limit, current_measurement_overload, voltage_measurement_overload, invalid_probe, invalid_calibration, inter_processor_communication_error, field_measurement_communication_error, probe_eeprom_read_error, r2_less_than_minimum_allowable)

Class object representing the questionable status register

class lakeshore.fast_hall_controller.ContactCheckManualParameters(excitation_type, excitation_start_value, excitation_end_value, compliance_limit, number_of_points, excitation_range='AUTO', measurement_range='AUTO', min_r_squared=0.9999, blanking_time=0.002)

Class object representing parameters used for manual Contact Check run methods.

__init__(excitation_type, excitation_start_value, excitation_end_value, compliance_limit, number_of_points, excitation_range='AUTO', measurement_range='AUTO', min_r_squared=0.9999, blanking_time=0.002)

The constructor for ContackCheckManualParameters class.

Args:
excitation_type (str):
  • The excitation type used for the measurement. Options are:
  • “CURRENT”
  • “VOLTAGE”
excitation_start_value (float):
The starting excitation value For voltage -10.0 to 10.0 V For current -100e-3 to 100e-3 A
excitation_end_value (float):
The ending excitation value For voltage -10.0 to 10.0 V For current -100e-3 to 100e-3 A
excitation_range (float or str):
  • Excitation range based on the excitation type. Options are:
  • “AUTO”: sets the range to the best fit range for a given excitation value
  • floating point number of
    • volts in the range of 0 to 10.0V: voltage excitation
    • amps in the range of -100e-3 to 100e-3 A: current excitation
measurement_range (float or str):
  • Measurement range based on the excitation type. Options are:
  • “AUTO”: sets the range to the best fit range for a given excitation value
  • floating point number of
    • amps in the range of 0 to 100e-3A: voltage excitation
    • volts in the range of 0 to 10.0V: current excitation
compliance_limit (float):
For voltage excitation, specify the current limit 100e-9 to 100e-3 A For current excitation, specify the voltage compliance 1.00 to 10.0 V
number_of_points (int):
The number of points to measure between the excitation start and end. 0 - 100
min_r_squared (float):
The minimum R^2 desired. Default is 0.9999.
blanking_time (float or str):
  • The time in seconds to wait for hardware to settle before gathering readings. Range of time is 0.5 ms - 300 s with a resolution of 0.1 ms. Options are:
  • “DEF” (Default) = 2 ms
  • “MIN” = 0.5 ms
  • “MAX” = 300 s
  • floating point number of seconds
class lakeshore.fast_hall_controller.ContactCheckOptimizedParameters(max_current=0.1, max_voltage=10, number_of_points=11, min_r_squared=0.9999)

Class object representing parameters used for optimized Contact Check run methods

__init__(max_current=0.1, max_voltage=10, number_of_points=11, min_r_squared=0.9999)

The constructor for ContactCheckOptimizedParameters class.

Args:
max_current(float or str):
  • A ‘not to exceed’ output current value for the auto algorithm to use. Options are:
  • “MIN” = 1 uA
  • “MAX” = 100 mA
  • “DEF” (Default) = 100 mA
  • floating point number of amps
max_voltage(float or str):
  • A ‘not to exceed’ output voltage value for the auto algorithm to use. Options are:
  • “MIN” = 1 V
  • “MAX” = 10 V
  • “DEF” (Default) = 10 V
  • floating point number of volts
number_of_points(int or str):
  • The number of points to measure between the excitation start and end. Options are:
  • “MIN” = 2
  • “MAX” = 100
  • “DEF” (Default) = 11
  • integer number of points
min_r_squared(float):
The minimum R^2 desired. Default is 0.9999.
class lakeshore.fast_hall_controller.FastHallManualParameters(excitation_type, excitation_value, user_defined_field, compliance_limit, excitation_range='AUTO', excitation_measurement_range='AUTO', measurement_range='AUTO', max_samples=100, resistivity='"NaN"', blanking_time=0.002, averaging_samples=60, sample_thickness=0, min_hall_voltage_snr=30)

Class object representing parameters used for running manual FastHall measurements

__init__(excitation_type, excitation_value, user_defined_field, compliance_limit, excitation_range='AUTO', excitation_measurement_range='AUTO', measurement_range='AUTO', max_samples=100, resistivity='"NaN"', blanking_time=0.002, averaging_samples=60, sample_thickness=0, min_hall_voltage_snr=30)

The constructor for FastHallManualParameters class

Args:
excitation_type (str):
  • The excitation type used for the measurement. Options are:
  • “CURRENT”
  • “VOLTAGE”
excitation_value(float):
For voltage -10.0 to 10.0 V For current -100e-3 to 100e-3 A
excitation_range (float or str):
  • Excitation range based on the excitation type. Options are:
  • “AUTO”: sets the range to the best fit range for a given excitation value
  • floating point number of
    • volts in the range of 0 to 10.0V for voltage excitation,
    • amps in the range of -100e-3 to 100e-3 A for current excitation
excitation_measurement_range (float or str):
  • Excitation measurement range based on the excitation type. Options are:
  • “AUTO”: sets the range to the best fit range for a given excitation value
  • floating point number of
    • volts in the range of 0 to 10.0V: voltage excitation
    • amps in the range of -100e-3 to 100e-3 A: current excitation
measurement_range (float or str):
  • Measurement range based on the excitation type. Options are:
  • “AUTO”: sets the range to the best fit range for a given excitation value
  • floating point number of
    • amps in the range of 0 to 100e-3A: voltage excitation
    • volts in the range of 0 to 10.0V: current excitation
compliance_limit (float):
For voltage excitation, specify the current limit 100e-9 to 100e-3 A For current excitation, specify the voltage compliance 1.00 to 10.0 V
user_defined_field (float):
The field, in units of Tesla, the sample is being subjected to. Used for calculations.
max_samples(int):
When minimumSnr is omitted or Infinity (‘INF’), the total number of samples to average 1 - 1000 When minimumSnr is specified, the maximum number of samples to average 10 - 1000. Default is 100
resistivity (float):
The resistivity of the sample in units of Ohm*Meters (bulk) of Ohms Per Square (sheet). Used for calculations. Measure this value using the RESistivity SCPI subsystem. Defaults to ‘Nan’ (not a number) which will propagate through calculated values
blanking_time (float or str):
  • The time in seconds to wait for hardware to settle before gathering readings. Range of time is 0.5 ms - 300 s with a resolution of 0.1 ms. Options are:
  • “DEF” (Default) = 2 ms
  • “MIN” = 0.5 ms
  • “MAX” = 300 s
  • floating point number in seconds
averaging_samples (int):
The number of voltage compensation samples to average. Only applied for excitation type voltage. 1 - 120. Default is 60.
sample_thickness (float):
Thickness of the sample in meters. 0 to 10E-3 m Default is 0 m
min_hall_voltage_snr (float or str):
  • The desired signal to noise ratio of the measurement calculated using average hall voltage / error of mean 1 - 1000. Options are:
  • “INF” (Infinity)
  • “DEF” (Default) = 30
  • floating point number to represent the ratio
class lakeshore.fast_hall_controller.FastHallLinkParameters(user_defined_field, measurement_range='AUTO', max_samples=100, min_hall_voltage_snr=30, averaging_samples=60, sample_thickness='DEF')

Class object representing parameters used for running FastHall Link measurements

__init__(user_defined_field, measurement_range='AUTO', max_samples=100, min_hall_voltage_snr=30, averaging_samples=60, sample_thickness='DEF')

The constructor for FastHallLinkParameters class

Args:
user_defined_field (float):
The field, in units of Tesla, the sample is being subjected to. Used for calculations.
measurement_range (float or str):
For voltage excitation, specify the current measurement range 0 to 100e-3 A For current excitation, specify the voltage measurement range 0 to 10.0 V. Defaults to ‘AUTO’
max_samples(int):
When minimumSnr is omitted or Infinity (‘INF’), the total number of samples to average 1 - 1000 When minimumSnr is specified, the maximum number of samples to average 10 - 1000 Defaults to 100
min_hall_voltage_snr (float or str):
  • The desired signal to noise ratio of the measurement calculated using average hall voltage / error of mean 1 - 1000. Options are:
  • “INF” (Infinity)
  • “DEF” (Default) = 30
  • floating point number to represent the ratio
averaging_samples (int):
The number of voltage compensation samples to average. Only applied for excitation type voltage. 1 - 120. Defaults to 60
sample_thickness (float):
Thickness of the sample in meters. 0 to 10E-3 m Default is the last run resistivity measurement’s sample thickness.
class lakeshore.fast_hall_controller.FourWireParameters(contact_point1, contact_point2, contact_point3, contact_point4, excitation_type, excitation_value, compliance_limit, excitation_range='AUTO', measurement_range='AUTO', excitation_measurement_range='AUTO', blanking_time=0.002, max_samples=100, min_snr=30, excitation_reversal=True)

Class object representing parameters used for running Four Wire measurements

__init__(contact_point1, contact_point2, contact_point3, contact_point4, excitation_type, excitation_value, compliance_limit, excitation_range='AUTO', measurement_range='AUTO', excitation_measurement_range='AUTO', blanking_time=0.002, max_samples=100, min_snr=30, excitation_reversal=True)

The constructor for FourWireParameter class.

Args:
contact_point1 (int):
Excitation +. Valid contact points are: 1, 2, 3, 4, 5, or 6. Cannot be the same as Contact Point 2.
contact_point2 (int):
Excitation - Valid contact points are: 1, 2, 3, 4, 5, or 6. Cannot be the same as Contact Point 1.
contact_point3 (int):
Voltage Measure/Sense +. Valid contact points are: 1, 2, 3, 4, 5, or 6. Cannot be the same as Contact Point 4.
contact_point4 (int):
Voltage Measure/Sense -. Valid contact points are: 1, 2, 3, 4, 5, or 6. Cannot be the same as Contact Point 3.
excitation_type (str):
  • The excitation type used for the measurement. Options are:
  • “CURRENT”
  • “VOLTAGE”
excitation_value(float):
For voltage -10.0 to 10.0 V For current -100e-3 to 100e-3 A
excitation_range (float or str):
  • Excitation range based on the excitation type. Options are:
  • “AUTO”: sets the range to the best fit range for a given excitation value
  • floating point number of
    • volts in the range of 0 to 10.0V for voltage excitation,
    • amps in the range of -100e-3 to 100e-3 A for current excitation
measurement_range (float or str):
  • Measurement range based on the excitation type. Options are:
  • “AUTO”: sets the range to the best fit range for a given excitation value
  • floating point number of
    • amps in the range of 0 to 100e-3A: voltage excitation
    • volts in the range of 0 to 10.0V: current excitation
excitation_measurement_range (float or str):
  • Excitation measurement range based on the excitation type. Options are:
  • “AUTO”: sets the range to the best fit range for a given excitation value
  • floating point number of
    • volts in the range of 0 to 10.0V: voltage excitation
    • amps in the range of -100e-3 to 100e-3 A: current excitation
compliance_limit (float):
For voltage excitation, specify the current limit 100e-9 to 100e-3 A For current excitation, specify the voltage compliance 1.00 to 10.0 V
blanking_time (float or str):
  • The time in seconds to wait for hardware to settle before gathering readings. Range of time is 0.5 ms - 300 s with a resolution of 0.1 ms. Options are:
  • “DEF” (Default)= 2 ms
  • “MIN” = 0.5 ms
  • “MAX” = 300 s
  • floating point number in seconds
max_samples(int):
When minimumSnr is omitted or Infinity, the total number of samples to average 1 - 1000 When minimumSnr is specified, the maximum number of samples to average 10 - 1000. Default is 100
min_snr (float or str):
  • The desired signal to noise ratio of the measurement resistance, calculated using measurement average / error of mean 1 - 1000. Options are:
  • “INF” (Infinity)
  • “DEF” (Default)= 30
  • floating point number to represent the ratio
excitation_reversal (bool):
True = Reverse the excitation to generate the resistance. False = no excitation reversal
class lakeshore.fast_hall_controller.DCHallParameters(excitation_type, excitation_value, compliance_limit, averaging_samples, user_defined_field, excitation_range='AUTO', excitation_measurement_range='AUTO', measurement_range='AUTO', with_field_reversal=True, resistivity='"NaN"', blanking_time=0.002, sample_thickness=0)

Class object representing parameters used for running DC Hall measurements

__init__(excitation_type, excitation_value, compliance_limit, averaging_samples, user_defined_field, excitation_range='AUTO', excitation_measurement_range='AUTO', measurement_range='AUTO', with_field_reversal=True, resistivity='"NaN"', blanking_time=0.002, sample_thickness=0)

The constructor for DCHallParameters.

Args:
excitation_type (str):
  • The excitation type used for the measurement. Options are:
  • “CURRENT”
  • “VOLTAGE”
excitation_value(float):
For voltage -10.0 to 10.0 V For current -100e-3 to 100e-3 A
excitation_range (float or str):
  • Excitation range based on the excitation type. Options are:
  • “AUTO”: sets the range to the best fit range for a given excitation value
  • floating point number of
    • volts in the range of 0 to 10.0V for voltage excitation,
    • amps in the range of -100e-3 to 100e-3 A for current excitation
excitation_measurement_range (float or str):
  • Excitation measurement range based on the excitation type. Options are:
  • “AUTO”: sets the range to the best fit range for a given excitation value
  • floating point number of
    • volts in the range of 0 to 10.0V: voltage excitation
    • amps in the range of -100e-3 to 100e-3 A: current excitation
measurement_range (float or str):
  • Measurement range based on the excitation type. Options are:
  • “AUTO”: sets the range to the best fit range for a given excitation value
  • floating point number of
    • amps in the range of 0 to 100e-3A: voltage excitation
    • volts in the range of 0 to 10.0V: current excitation
compliance_limit (float):
For voltage excitation, specify the current limit 100e-9 to 100e-3 A For current excitation, specify the voltage compliance 1.00 to 10.0 V
averaging_samples(int):
The number of samples to average 1-1000
user_defined_field(float):
The field, in units of Tesla, the sample is being subjected to. Used for calculations.
with_field_reversal (bool):
Specifies whether or not to apply reversal field. Default is true
resistivity(float):
The resistivity of the sample in units of Ohm*Meters (bulk) of Ohms Per Square (sheet). Used for calculations. Measure this value using the RESistivity SCPI subsystem. Defaults to ‘NaN’ (not a number) which will propagate through calculated values.
blanking_time (float or str):
  • The time in seconds to wait for hardware to settle before gathering readings. Range of time is 0.5 ms - 300 s with a resolution of 0.1 ms. Options are:
  • “DEF” (Default) = 2 ms
  • “MIN” = 0.5 ms
  • “MAX” = 300 s
  • floating point number in seconds
sample_thickness (float):
Thickness of the sample in meters. 0 to 10e-3 m. Default is 0m
class lakeshore.fast_hall_controller.ResistivityManualParameters(excitation_type, excitation_value, compliance_limit, excitation_range='AUTO', excitation_measurement_range='AUTO', measurement_range='AUTO', max_samples=100, blanking_time=0.002, sample_thickness=0, min_snr=30, **kwargs)

Class object representing parameters used for running manual Resistivity measurements

__init__(excitation_type, excitation_value, compliance_limit, excitation_range='AUTO', excitation_measurement_range='AUTO', measurement_range='AUTO', max_samples=100, blanking_time=0.002, sample_thickness=0, min_snr=30, **kwargs)

The constructor for ResistivityManualParameters class.

Args:
excitation_type (str):
  • The excitation type used for the measurement. Options are:
  • “CURRENT”
  • “VOLTAGE”
excitation_value(float):
For voltage -10.0 to 10.0 V For current -100e-3 to 100e-3 A
excitation_range (float or str):
  • Excitation range based on the excitation type. Options are:
  • “AUTO”: sets the range to the best fit range for a given excitation value
  • floating point number of
    • volts in the range of 0 to 10.0V for voltage excitation,
    • amps in the range of -100e-3 to 100e-3 A for current excitation
excitation_measurement_range (float or str):
  • Excitation measurement range based on the excitation type. Options are:
  • “AUTO”: sets the range to the best fit range for a given excitation value
  • floating point number of
    • volts in the range of 0 to 10.0V: voltage excitation
    • amps in the range of -100e-3 to 100e-3 A: current excitation
measurement_range (float or str):
  • Measurement range based on the excitation type. Options are:
  • “AUTO”: sets the range to the best fit range for a given excitation value
  • floating point number of
    • amps in the range of 0 to 100e-3A: voltage excitation
    • volts in the range of 0 to 10.0V: current excitation
compliance_limit (float):
For voltage excitation, specify the current limit 100e-9 to 100e-3 A For current excitation, specify the voltage compliance 1.00 to 10.0 V
max_samples(int):
When minimumSnr is omitted or Infinity (‘INF’), the total number of samples to average 1 - 1000 When minimumSnr is specified, the maximum number of samples to average 10 - 1000. Default is 100
blanking_time (float or str):
  • The time in seconds to wait for hardware to settle before gathering readings. Range of time is 0.5 ms - 300 s with a resolution of 0.1 ms. Options are:
  • “DEF” (Default) = 2 ms
  • “MIN” = 0.5 ms
  • “MAX” = 300 s
  • floating point number in seconds
averaging_samples (int):
The number of voltage compensation samples to average. Only applied for excitation type voltage. 1 - 120. Default is 60
sample_thickness (float):
Thickness of the sample in meters. 0 to 10E-3 m. Default is 0 m
min_snr (float or str):
  • The desired signal to noise ratio of the measurement calculated using average resistivity / error of mean 1 - 1000. Options are:
  • “INF” (Infinity)
  • “DEF” (Default) = 30
  • floating point number to represent the ratio
Kwargs:
width(float):
The width of the sample in meters. Greater than 0
separation(float):
The distance between the sample’s arms in meters. Greater than 0
class lakeshore.fast_hall_controller.ResistivityLinkParameters(measurement_range='AUTO', sample_thickness=0, min_snr=30, max_samples=100)

Class object representing parameters used for running manual Resistivity measurements

__init__(measurement_range='AUTO', sample_thickness=0, min_snr=30, max_samples=100)

The constructor for ResistivityLinkParameters class.

Args:
measurement_range (float or str):
  • Measurement range based on the excitation type. Options are:
  • “AUTO”: sets the range to the best fit range for a given excitation value
  • floating point number of
    • amps in the range of 0 to 100e-3A: voltage excitation
    • volts in the range of 0 to 10.0V: current excitation
sample_thickness (float):
Thickness of the sample in meters. 0 to 10E-3 m. Default is 0 m
min_snr (float or str):
  • The desired signal to noise ratio of the measurement calculated using average resistivity / error of mean 1 - 1000. Options are:
  • “INF” (Infinity)
  • “DEF” (Default)= 30
  • floating point number to represent the ratio
max_samples(int):
When minimumSnr is omitted or Infinity (‘INF’), the total number of samples to average 1 - 1000 When minimumSnr is specified, the maximum number of samples to average 10 - 1000 Default is 100
class lakeshore.fast_hall_controller.StatusByteRegister(error_available, questionable_summary, message_available_summary, event_status_summary, master_summary, operation_summary)

Class object representing the status byte register

__init__(error_available, questionable_summary, message_available_summary, event_status_summary, master_summary, operation_summary)

Initialize self. See help(type(self)) for accurate signature.

class lakeshore.fast_hall_controller.StandardEventRegister(operation_complete, query_error, device_specific_error, execution_error, command_error, power_on)

Class object representing the standard event register

__init__(operation_complete, query_error, device_specific_error, execution_error, command_error, power_on)

Initialize self. See help(type(self)) for accurate signature.