A low frequency vibrating sample magnetometer

Abstract

A new version of the vibrating sample magnetometer with a superconducting NbTi magnet has been constructed. The vibration is performed with a synchronous motor and a crank arrangement at a fixed frequency of 5 Hz and the amplitude is chosen to give the greatest possible content of first harmonic in the pickup signal. In this way the magnitude of the signal is made independent of small variations in the vibration amplitude. The relative accuracy of the system is 0.1%. No image effect (<0.1%) has been observed in the NbTi solenoid. The working temperature region of the instrument is 1.5-300K.