HTS-SQUID vector magnetometer with low crosstalk configuration

Abstract

Abstract We propose an HTS-SQUID vector magnetometer with a new configuration reducing the crosstalk between a pickup coil of one SQUID and feedback coils of other SQUIDs. The new configuration is designed to mount three SQUIDs at symmetric positions where the crosstalk should be ideally zero while keeping minimal height of a probe head. In an actual HTS-SQUID magnetometer, however, either pickup coil or feedback coil is inevitably dislocated from the ideal symmetric positions. Numerical simulation of crosstalk revealed that the new configuration has smaller crosstalk than that of a conventional cubic configuration even if the positioning error from the ideal symmetric positions is as small as 1 mm. Three types of SQUID vector magnetometer were fabricated and their crosstalk was measured. The averaged crosstalk of a SQUID vector magnetometer using the new configuration was actually improved by about one order of magnitude as compared with the conventional cubic configuration.