[14a-D221-1~12] 6.2 Carbon-based thin films

△ [14a-D221-9] Fabrication of Diamond SQUID using Single Step Josephson Junctions

〇(B)Yasuhiro Takahashi¹, Shotaro Amano¹, Aoi Morishita¹, Taisuke Kageura^1,2, Yoshihiko Takano², Minoru Tachiki², Shuuichi Ooi², Shunichi Arisawa², Hiroshi Kawarada^1,3 (1.Waseda Univ., 2.NIMS, 3.Zaiken)

Keywords:Diamond, Superconductivity, Superconducting Quantum Interference Device

SQUID which is a magnetic sensor capable of detecting an extremely small magnetic field is one of the typical superconducting devices that have already been put to practical use. The current mainstream Nb-based materials are subject to deterioration in characteristics due to oxidation and physical contact. Therefore, we have fabricated and demonstrated the operation of highly robust SQUIDs by diamond, which has excellent oxidation resistance and wear resistance. In this study, we fabricated SQUIDs using a single-step Josephson junction with simpler shape and higher uniformity of characteristics than the conventional structure with micro-trench on the substrate. They operated above liquid helium temperature. Therefore, the improvement of uniformity and reproducibility of SQUIDs were demonstrated.