[9p-N404-1~15] 11.4 Analog applications and their related technologies

2:00 PM - 2:15 PM JST(5:00 AM - 5:15 AM UTC)

[9p-N404-3] Development of liquid-helium-free cryogenic current comparator

〇Yuma Okazaki¹, Takehiko Oe¹, Nobu-Hisa Kaneko¹ (1.AIST)

Keywords:

cryogenic current comparator,SQUID,quantum electrical standard

The cryogenic current comparator (CCC) is a superconducting electrical circuit used for precision resistance metrology, composed of a SQUID magnetometer and magnetic shielding. It is typically cooled by immersion in liquid helium; however, due to the recent helium shortage, long-duration measurements are becoming increasingly difficult. In this work, we developed a new cryogenic system in which a gas chamber is installed inside a cryogen-free refregerator cooled with a pulse tube precooler, using gaseous helium as a thermal conduction medium. This system enables long-term operation without consuming liquid helium.