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Generation and Suppression of Decoherence in Artificial Environment for Qubit System

Yasushi Kondo·Mikio Nakahara·Shogo Tanimura·Sachiko Kitajima·Chikako Uchiyama·Fumiaki Shibata
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Abstract

It is known that a quantum system with finite degrees of freedom can simulate a composite of a system and an environment if the state of the hypothetical environment is randomized by external manipulation. We show theoretically that any phase decoherence phenomena of a single qubit can be simulated with a two-qubit system and demonstrate experimentally two examples: one is phase decoherence of a single qubit in a transmission line, and the other is that in a quantum memory. We perform NMR experiments employing a two-spin molecule and clearly measure decoherence for both cases. We also prove experimentally that the bang-bang control efficiently suppresses decoherence.

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Yasushi Kondo, Mikio Nakahara, Shogo Tanimura, Sachiko Kitajima, Chikako Uchiyama, Fumiaki Shibata. 2007-02-10. Generation and Suppression of Decoherence in Artificial Environment for Qubit System. https://doi.org/10.1143/jpsj.76.074002

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