TY - GEN
T1 - Improvement of sensitivity for a compact magnetometer using HTS-SQUID with rotating sample
AU - Hamasaki, Daichi
AU - Okamoto, Naohiro
AU - Saari, Mohd Mawardi
AU - Sakai, Kenji
AU - Kiwa, Toshihiko
AU - Tsukada, Keiji
N1 - Copyright:
Copyright 2013 Elsevier B.V., All rights reserved.
PY - 2013
Y1 - 2013
N2 - We previously reported a compact magnetometer using HTS-SQUID with a rotating sample for routine testing. In this study, we have improved the detection limit of the system to detect a very weak secondary magnetic field from diamagnetic material. The system consisted of a rotating sample table, a magnet with a pick-up coil, and an HTS-SQUID. The six sample cases can be fixed to a turntable using sample arms to enable multiple-detection. By rotating the sample, the velocity of the sample passing above the pick-up coil could be increased compared to the vibrating-sample method. The pick-up coil was directly coupled to a superconducting input coil of the HTS-SQUID to transfer the detected signal to the HTS-SQUID. The HTS-SQUID attached to a sensor probe was cooled by liquid nitrogen in a Dewar vessel, which was enclosed in a bilayer magnetically shielded cylindrical box. To improve the detection limit of the magnetometer's susceptibility, the noise of the applied magnetic fields was reduced, the pick-up coil shape optimized, and the accuracy of rotation speed was increased. As a result, the signal and noise ratio was improved and the magnetometer showed a high sensitivity and accuracy.
AB - We previously reported a compact magnetometer using HTS-SQUID with a rotating sample for routine testing. In this study, we have improved the detection limit of the system to detect a very weak secondary magnetic field from diamagnetic material. The system consisted of a rotating sample table, a magnet with a pick-up coil, and an HTS-SQUID. The six sample cases can be fixed to a turntable using sample arms to enable multiple-detection. By rotating the sample, the velocity of the sample passing above the pick-up coil could be increased compared to the vibrating-sample method. The pick-up coil was directly coupled to a superconducting input coil of the HTS-SQUID to transfer the detected signal to the HTS-SQUID. The HTS-SQUID attached to a sensor probe was cooled by liquid nitrogen in a Dewar vessel, which was enclosed in a bilayer magnetically shielded cylindrical box. To improve the detection limit of the magnetometer's susceptibility, the noise of the applied magnetic fields was reduced, the pick-up coil shape optimized, and the accuracy of rotation speed was increased. As a result, the signal and noise ratio was improved and the magnetometer showed a high sensitivity and accuracy.
KW - HTS-SQUID
KW - magnetic susceptibility
KW - magnetometer
KW - rotating sample
UR - http://www.scopus.com/inward/record.url?scp=84885233915&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84885233915&partnerID=8YFLogxK
U2 - 10.1109/ISEC.2013.6604306
DO - 10.1109/ISEC.2013.6604306
M3 - Conference contribution
AN - SCOPUS:84885233915
SN - 9781467363716
T3 - 2013 IEEE 14th InternationalSuperconductive Electronics Conference, ISEC 2013
BT - 2013 IEEE 14th InternationalSuperconductive Electronics Conference, ISEC 2013
T2 - 2013 IEEE 14th InternationalSuperconductive Electronics Conference, ISEC 2013
Y2 - 7 July 2013 through 11 July 2013
ER -