Design, fabrication and experimental demonstration of a highly sensitive SQUID-based accelerometer

Abstract

Abstract In this paper, a newly designed accelerometer based on a SQUID detection technology and the experimental results are presented. The levitated proof mass was manufactured in the shape that combines a disk and a cylinder on the basis of an earlier patent by the authors. The advantage of this shape is, given that the bottom part is cylindrical, even if the proof mass is mounted mechanically tilted, it can be moved to the center depending on the magnetic flux. The inside of the accelerometer is unobservable after the sealing of the superconducting housing; therefore, the initial set current values on both the solenoid and flat spiral coil are crucial. It was easily able to determine the levitation status at equilibrium position of the proof mass by investigating the inductance change according the persistent current for sensing and solenoid coils. At the levitation status, the movement of the proof mass caused by an external acceleration could be detected with a SQUID optimization. Accordingly, levitation experimental results and the flux noise spectra of the levitated proof mass are described.