In pulsed fields, torque magnetometry is a highly sensitive technique for measuring magnetically anisotropic materials.
The unloaded resonant frequency of 250-300kHz allows for fast response in pulsed magnetic fields (65T – 8ms rise time). A balanced Wheatstone bridge and ground shielding to prevent inductive/capacitive cross talk are used to detect a torque signal on the order of 10-13 Nm on sub-µg samples. The noise floor of a typical balanced bridge resistance measurement is less than 5mΩ/500Ω. The torque magnetometry technique has been successfully used to detect anisotropy changes in strongly correlated magnetic systems and resolve quantum oscillations for mapping out Fermi surface topology.
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Last modified on 27 December 2022