Magnetic Properties Measurement System (MPMS-3)

Specifications:

• Temperature range: 1.8 K - 1000 K
  • 1.8 K - 400 K in standard mode.
  • Room temperature to 1000 K in oven mode.
• Maximum applied magnetic field: 7 T
• 3 modes: DC, VSM, or AC:
  • DC mode
    • DC moment range: 5 x 10^-11 Am² to 2 x 10^-3 Am² (sensitivity depends on applied field)
  • VSM mode (widest dynamic range)
    • VSM moment range: 1 x 10^-11 Am² to 1 x 10^-1 Am² (sensitivity depends on applied field)
  • AC mode (for magnetic susceptibility)
    • AC Frequency Range:  0.1-1000 Hz
    • AC Field Amplitude:  0.1-10 Oe
• Rapid field and temperature ramping.
• Rotator head for moment versus angle measurements.

Measurement Types:

The MPMS is used primarily for magnetic mineral identification based on low-temperature crystallographic transitions (e.g., the Verwey transition in magnetite at about 120 K), and for characterizing particle size distributions, especially for samples containing ultrafine-grained superparamagnetic grains.

Typically used to measure:

• Field cooled & Zero-field cooled (FC-ZFC) curves in zero-field (although can be run in a small bias field).
• Room-Temperature Saturation Isothermal Remanent Magnetization (RT-SIRM) curves.
• Frequency dependence of magnetic susceptibility with varying temperature.
• Field dependence of susceptibility with varying temperature.
• Hysteresis loops to 7 T and at variable temperature.
• Moment versus angle measurements.

More information about the MPMS-3 system can be found in the IRM Quarterly Vol. 33, No. 4 and on the Quantum Design website.