# Coherent quantum phase slip ? Josephson effect’s complete conjugate Jaw-Shen Tsai (NEC/Riken)

Salle E244 - 24, rue Lhomond - 13h30

Jeudi 22 novembre

We are carrying out studies of coherent quantum phase slip (CQPS) effect which is
the exact quantum mechanical conjugate to the Josephson effect. It is a phenomenon
involving coherent tunneling of magnetic flux across a thin superconducting
wire, just like tunneling of Cooper-pair across thin insulator in the Josephson tunnel
junction.

The existence of CQPS was recently proposed theoretically. By utilizing CQPS, it is
expected that many quantum devices conjugate to the Josephson devices can be
realized. For example, quantum current standard conjugate to the Josephson voltage
standard, superconducting quantum charge detector conjugate to the superconducting
quantum flux detector (SQUID) and so on should be realized.
We have initiated experiments toward the detection of CQPS by utilizing several
superconducting materials.

Salle E244 - 24, rue Lhomond - 13h30