Quantum coherence in a single-Cooper-pair box: experiments in the frequency and time domains

被引：16

作者：

Nakamura, Y

Pashkin, YA

Tsai, JS

机构：

[1] NEC Corp Ltd, Fundamental Res Labs, Tsukuba, Ibaraki 3058501, Japan

[2] Japan Sci & Technol Corp JST, CREST, Kawaguchi, Saitama 3320012, Japan

来源：

PHYSICA B | 2000年 / 280卷 / 1-4期

关键词：

coherent oscillations; energy-level splitting; Josephson junction; two-level system;

D O I：

10.1016/S0921-4526(99)01790-1

中图分类号：

O469 [凝聚态物理学];

学科分类号：

070205 ;

摘要：

In a small superconducting electrode connected to a reservoir via a Josephson junction, we can realize an artificial two-level system in which two charge-number states of the electrode are coupled by Cooper-pair tunneling. We have investigated quantum coherence in the two-level system through two complementary experiments: (i) photon-assisted Cooper-pair-tunneling spectroscopy of the energy-level splitting in the frequency domain, and (ii) pulsed-gate control of the quantum state to observe the coherent oscillations in the time domain. Our results demonstrate the existence and the persistence of the coherence for at least similar to 30 cycles of the oscillation. (C) 2000 Elsevier Science B.V. All rights reserved.

引用

页码：405 / 409

页数：5

共 13 条

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