INTERFACING OF A CLOSED-CYCLE HELIUM REFRIGERATOR TO A VIBRATING SAMPLE MAGNETOMETER FOR LOW-TEMPERATURE (12-300 K) MAGNETIZATION STUDIES

A top-loading sample chamber tube, radiation shield and the vacuum shr oud for interfacing a closed-cyde helium refrigerator for use with a v ibrating sample magnetometer have been designed and fabricated. A lowe st temperature of 12 K is achieved at the sample. The eddy current eff ects in the copper sample chamber tube are minimized by the use of an electrically insulating epoxy resin medium. The sample temperature is measured by a GaAlAs diode sensor attached on a sensor mount which is inserted into the sample zone and kept in helium atmosphere. The vibra tions of the cryocooler's cold head are isolated from the vibrating sa mple magnetometer's head by incorporating a bellows. Using this facili ty the magnetic transitions of some rare earth elements have been meas ured and compared with the literature data.