Low-temperature Stepper Motor Operating in High Magnetic Field

Abstract

A stepper electric motor has been designed to rotate a sample in an experimental cell inside a cryostat with ³He pumping. The device based on a rotor with crossed electrical windings, operates in an external magnetic field generated by a superconducting magnet. A prototype of the motor was mounted on a microwave spectrometer with a rectangular resonator. Test angular dependence of the magnetic resonance spectrum was obtained in a well-studied weak ferromagnet \({\text{MnC}}{{{\text{O}}}_{3}}\) at temperatures 0.5–7.5 K in the range of angles ±100° from the initial position. Overheating of the cell and cryostat was studied and the heat release during operation of the mechanism was estimated.