Decoherence of flux qubits due to 1/f flux noise

被引：334

作者：

Yoshihara, F. ^{[1
]}

Harrabi, K.

Niskanen, A. O.

Nakamura, Y.

Tsai, J. S.

机构：

[1] RIKEN, Inst Phys & Chem Res, Wako, Saitama 3510198, Japan

[2] JST, CREST, Kawaguchi, Saitama 3320012, Japan

[3] VTT Tech Res Ctr Finland, Sensors, Espoo 02044, Finland

[4] NEC Corp Ltd, Fundamental & Environm Res Labs, Tsukuba, Ibaraki 3058501, Japan

来源：

PHYSICAL REVIEW LETTERS | 2006年 / 97卷 / 16期

关键词：

D O I：

10.1103/PhysRevLett.97.167001

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

We have investigated decoherence in Josephson-junction flux qubits. Based on the measurements of decoherence at various bias conditions, we discriminate contributions of different noise sources. We present a Gaussian decay function extracted from the echo signal as evidence of dephasing due to 1/f flux noise whose spectral density is evaluated to be about (10(-6)Phi(0))(2)/Hz at 1 Hz. We also demonstrate that, at an optimal bias condition where the noise sources are well decoupled, the coherence observed in the echo measurement is limited mainly by energy relaxation of the qubit.

引用

页数：4

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