AC Susceptibility
The AC Susceptometer option uses a small primary excitation coil to apply an AC field to a sample (typically 1mT at frequencies from 0.1 Hz 10000 Hz). A pair of secondary pick-up coils positioned close to the excitation coils are used to detect the sample response. The resultant signal is measured using a Lock-In amplifier with the in-phase and out-of-phase components of the signal corresponding to the real and imaginary components of the AC Susceptibility of the sample. An additional compensation coil is used to eliminate background signals.
