Improved Low-Frequency Noise of High-Tc SQUID Magnetometer with Serial Flux Dams

C.-H. Wu ； J.-H. Chen ； K.-L. Chen ； J.-C. Chen ； H.-E. Horng ； H.-C. Yang

《Chinese Journal of Physics》 43卷3S期 (2005/06) Pp. 675-680

並列摘要

We fabricated a serial low-noise direct-current superconducting quantum interference device (SQUID) magnetometer on a 10 mm x 10 mm SrTiO3 (100) bicrystal substrate. The magnetometer is directly coupled and the SQUIDs are in serial arrangement and with different junction widths. In order to suppress the vortex motion in the pickup loop, the width of pickup loop across grain boundary was 5 μm to form the flux dam. The noise was measured to investigate the effect of the serial flux dams on the low frequency noise characteristics. These results suggest flux dam can be fabricated using uniform serial junctions connected with pick-up loop. The serial SQUID arrays with flux dam also offer the advantage in reducing the low frequency 1/f noise of SQUID.