Magnetic & Electrical

Physical Properties Measurement System (PPMS, Quantum Design)

Our PPMS is our main workhorse for characterisation of magnetic and electrical properties of devices and materials.

• Interchangeable units for VSM and I/V measurements
• Superconducting magnet with applied field of up to 14T
• Liquid He cooling allows temperature range of 4-300K

Vibrating Sample Magnetometer (VSM) / Alternating Gradient Force Magnetometer (AGFM), Princeton Corp. Model 2900 MicroMag

This device is equipped with an electromagnet rather than a superconducting magnet like our PPMS. While the applied field therefore has a lower maximum value, it can be swept at a much greater rate, which allows for an interesting diversity of measurement modes.

• Interchangeable units for AGFM and VSM measurements
• Different probes available for measurement of magnetisation along x-axis and z-axis
• Maximum applied field of 1T
• Cryostat attachment allows cooling with liquid nitrogen
• Measurement modes include:
  • Conventional M-H loops
  • First-order reversal curves (FORCs)
  • Remanence Magnetisation
  • Time dependence measurements of magnetisation

Closed cycle refrigerator setup (CCR)

For basic electrical measurements such as I/V curves, sheet resistance and resistive switching experiments we operate a closed cycle refrigerator setup, with a water cooled magnet. The temperature range is limited to 4-300 K and the field to 850 mT, but the system is easier to use and does not require liquid Helium.

• Water cooled magnet (850mT)
• Temperature range of 4-320K
• Multiple measure modes: Hall effect and resistance in van der Pauw geometry, Lock-In amplifier for AC measurements

High temperature resistance setup

The system, designed in the group, is used for resistance vs. temperature measurements from 300-750K in a controlled gas atmosphere (Vacuum, O₂, N₂) allowing for resistance monitoring during post annealing. We can also introduce temperature gradients for simple Seebeck measurements.

• Resistance setup in bell jar (1-1000 mbar)
• 4 point linear probe geometry for I/V and Resistance measurements
• 2 point probes for Seebeck measurements