PREPARATION PROCEDURE FOR LOADING FLUX QUANTUM WEIGHTS ON PICONEWTON FORCE REALIZATION SYSTEM

摘要

We present a preparation procedure for loading flux quantum weights on piconewton force standard system, being developed at KRISS, including the micro-positioning of a cantilever device with a superconducting micro-ring. To locate the device at zero-magnetic-field position inside a high-field-gradient superconducting magnet, the behaviour of the mechanical resonance frequency of the device in magnetic fields were studied in a dynamic mode and used to probe the local magnetic field value at the device position. A vertical offset of a few hundred micrometers caused a shift of ～ 0.7 Hz to the resonance frequency of 1144.4 Hz, and was nulled by either additional uniform magnetic field or a z-axis nano-positioner. Nulling was also confirmed by a non-singular temperature dependence of the resonance frequency.