The DynaCoolTM Physical Properties Measurement System (PPMS) is a multifunctional instrument, able to measure the electromagnetic and thermodynamic properties of virtually any material under magnetic fields of up to ± 14 T and temperatures of 400 K – 1.8 K (and up to 1000 K in the case of DC magnetisation measurements). Unique in the UK, the MRF’s PPMS can characterise samples that have been irradiated, with activities < 0.1 MBq Co60. Currently installed modes allow for the measurement of sample: DC magnetisation; AC magnetic susceptibility; resistivity (and conductivity), V/I and dV/dI characteristics and Hall coefficient (as a function of field angle); heat capacity.
Applications:
Characterisation of superconducting (both high and low temperature), semiconducting, conducting and insulating materials across a wide parameter space in magnetic field and temperature. Extremely useful for the determination of superconductor critical parameters (critical temperature, field and current) and material phase transitions. Useful for probing material anisotropy by studying how electrical properties vary as a function of applied field angle.
Technical specifications:
- Maximum field of ± 14 T and ramp rate of ~0.01 T s-1. Field resolution of 0.0001 T. Maximum temperature of 400 K and minimum temperature of 1.8 K. 40 minutes to reach 1.8 K from 300 K. 0.1 % noise < 20 K, 0.02 % noise > 20 K.
- (DC) resistivity: Resistivity, conductance and conductivity measurements on up to 3 samples simultaneously and can supply currents of up to 5 mA. The system is capable of accurately and precisely measuring resistances of 10 μΩ – 4 MΩ.
- Horizontal rotator: (DC) Resistivity and (AC) Electrical Transport measurements as a function of applied magnetic field angle on up to 2 samples simultaneously. Angular precision to 0.05 degrees.
- AC measurement system: AC magnetic susceptibility and DC magnetisation of samples. AC drive magnetic field 10 – 10000 Hz, 10-3 T. Magnetic moment resolution of ~ 10 pA m2 in AC mode and ~ 5 nA m2 in DC mode.
- Vibrating sample magnetometer & VSM oven: DC magnetisation of samples at temperatures of up to 1000 K. With vibrations of amplitude 1–3 mm peak and frequency of 40 Hz, magnetic moment resolution of ~ 1 nA m2.
- Heat capacity: Specific heat capacity of samples of mass 1 – 200 mg, precise to ~ 5 %, < 2% typically. 10 nJ K-1 resolution.
