METHOD AND APPARATUS FOR MEASURING AC SUSCEPTIBILITY AND DC MAGNETIZATION OF A SAMPLE

摘要

A variable temperature, two-coil (126a and 126b), two position ac susceptometer has been used to also perform absolute dc moment measurements using an extraction measurement technique. Virtually no hardware modifications were required and the full ac measurement capability is maintained. The signal analysis for the moment measurement is done using a high speed digital voltmeter (124). The system can be configured to yield high resolution dc moment measurements to 25 ppm and sensitivities to better than 5 x 10<5> emu.