National Institute of Advanced Industrial Science and Technology

Japan Science and Technology Agency

Kagoshima University

Tokyo University of Science

Kazuyasu Tokiwa

Tsuneo Watanabe

Akira Iyo

Yasumoto Tanaka

Norio Terada

Naoto Kikuchi

Adrian Crisan

Parasharam Shirage

Athinarayan Sundaresan

Dilip Shivagan

Shiro Kawabata

A control method is proposed that controls inter-component phase difference solitons by using splitting or fusion caused by the interaction between inter-component phase difference solitons themselves, without the need for application of external energy. By using a line structure () in which an inter-component phase difference soliton propagation line through which an inter-component phase difference soliton (So) which can exist in a superconducting environment can travel is divided into a plurality of branch lines (-and-) at least at a branch end (Po) set in the middle of the line, an inter-component phase difference soliton (So) in a main line (M) which is an undivided line portion is allowed to be split and to enter the plurality of branch lines (-and-) without a supply of external energy, or inter-component phase difference solitons (Soand So) in the respective branch lines (-and-) are fused together without a supply of external energy, whereby an inter-component phase difference soliton (So) is allowed to propagate through the main line (M).

Method for controlling inter-component phase difference soliton and inter-component phase difference soliton circuit device

The length portion of part of a multiband superconductor lineis used as a closed circuit line part Rc that constitutes part of a closed circuit allowing passage of an electric current Io generated by an electric current source. Meantime, the line part extending and continuing into the closed circuit line part Rc is used as an open circuit line part Ro adapted to serve as an open circuit regarding the electric current source. By keeping the multiband superconductor lineunder a temperature environment falling short of the critical soliton temperature and injecting a nonequilibrium electric current Io from the electric current sourceinto the closed circuit line part of the multiband superconductor line, it is rendered possible to induce generation of an interband phase different soliton So. The generated interband phase difference soliton So is forwarded as separated from the electric current Io to the open circuit line part Ro and is made to run therein. The open circuit line part Ro is provided with a Josephson junctionand consequently enabled to induce extinction of the interband phase different soliton So that has advanced thereto, during which time the voltage generated by the AC Josephson effect is detected with the voltage detecting device

Method of generation and method of detection of interband phase difference solition and interband phase difference circuit

A quantum Turing machine constituted using a quantum bit created by localizing a phase difference soliton S between superconducting electrons existing in each of multiple of bands in a ring Rthat includes a ring main body Rformed of a superconductor, and well-shaped portions W, Wformed with a reduced line-width at at least two positions on the ring main body R, can easily constitute a quantum bit, can surely execute a basic logical operation, has multiple-bit capability and, moreover, can ensure sufficient time for executing a quantum algorithm.

Quantum turing machine

Growing community of inventors

Tokyo, Japan

Kazuyasu Tokiwa