Measurement of Hall Effect and Sample Mobility
Lake Shore M91 MeasureReady® FastHall™ Measurement Controller for PPMS
The Lake Shore Cryotronics MeasureReady M91 FastHall controller delivers significantly higher levels of precision, speed, and convenience as compared to traditional Hall effect measurement solutions. Combining all the necessary Hall measurement functions into a single instrument, the M91 automatically executes measurements and calculates the final Hall and mobility parameters. The instrument eliminates manual trial-and-error steps, and ensures that measurements are always made under optimal conditions for the sample.
The M91 and its patented FastHall technology eliminates the need to reverse the magnetic field during the measurement. This is particularly beneficial when using the M91 with the superconducting magnet of a PPMS, allowing for much faster analysis of low-mobility material samples in van der Pauw (vdP) wired geometries.
Two options are available to easily integrate the M91 into a PPMS:
- Standard resistance: uses a Lake Shore feedthrough box to connect the M91 to the PPMS
- High resistance: uses low-noise, fully guarded custom probe for your PPMS
Features
- MeasureLINK™ software integrates with MultiVu™ in all PPMS platforms
- No need for field reversal during measurement
- Automatically selects optimal excitation and measurement levels, checks sample contact quality, and provides complete Hall analysis
- Calculates derived parameters for vdP and Hall bar samples
- Available as High Resistivity option which includes custom Lake Shore Hall insert
Models
Standard Resistance
The standard resistance M91 supports both van der Pauw (4 connections) and Hall bar (6 connections) geometries. These samples are wired to Quantum Design’s PPMS sample puck. When inserted into the PPMS, the sample connections are present on the LEMO connector on the side of the PPMS. The DB25-M91-TRIAX feedthrough box enables these pins to connect to the M91.
- Supports van der Pauw and Hall bar samples
- Resistance range: 10 mΩ to 10 MΩ
- Cut measurement time up to one half with no field reversal needed
- Switching technique minimizes thermal drift
High Resistance
The high resistance M91 HR supports both van der Pauw (4 connections) and Hall bar (6 connections) geometries, while providing a larger resistance range than the standard model. This version comes equipped with a custom Lake Shore Hall insert to be used within your PPMS. The insert is fully-guarded from instrument to sample for ultra-low noise measurements.
- Supports van der Pauw and Hall bar samples
- Resistance range: 10 mΩ to 200 GΩ
- Best performance for low-noise, low-current measurements
- Fastest measurements with reduced settling times
- Switching technique minimizes thermal drift
