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Persistent Supercurrent Atom Chip

T. Mukai·C. Hufnagel·A. Kasper·T. Meno·A. Tsukada·K. Semba·F. Shimizu
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Abstract

Rubidium 87 atoms are trapped in an Ioffe-Pritchard potential generated with a persistent supercurrent that flows in a loop circuit patterned on a sapphire surface. The superconducting circuit is a closed loop made of 100 micro meter wide MBE-grown MgB2 stripe carrying a supercurrent of 2.5 A. To control the supercurrent in the stripe, an on-chip thermal switch operated by a focused argon-ion laser is developed. The switch operates as an on/off switch of the supercurrent, or as a device to set the current to a specific value with the aid of an external magnetic field. The current can be set even without an external source if the change is in decreasing direction.

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T. Mukai, C. Hufnagel, A. Kasper, T. Meno, A. Tsukada, K. Semba, F. Shimizu. 2007-02-06. Persistent Supercurrent Atom Chip. https://doi.org/10.1103/physrevlett.98.260407

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