Lifetime and Coherence of Two-Level Defects in a Josephson Junction
Lifetime and Coherence of Two-Level Defects in a Josephson Junction
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DOI：
10.1103/physrevlett.105.177001
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发表时间：
2010-10-19
影响因子：
8.6
通讯作者：
Katz, Nadav
中科院分区：
文献类型：
--
作者：
Shalibo, Yoni;Rofe, Ya'ara;Katz, Nadav
我们测量了Josephson相量子比特绝缘势垒中两能级缺陷态（TLSs）的寿命（T(1)）和相干性（T(2)），并比较了两个系统之间的相互作用强度。我们发现平均衰减时间与相应的相互作用强度呈幂律依赖关系，而对于平均相干时间，我们发现在中间耦合强度下是最优的。我们使用标准TLS模型解释了寿命和相干性结果，包括声子的偶极子辐射和能量参数对环境波动的反相关依赖。
We measure the lifetime (T(1)) and coherence (T(2)) of two-level defect states (TLSs) in the insulating barrier of a Josephson phase qubit and compare to the interaction strength between the two systems. We find for the average decay times a power-law dependence on the corresponding interaction strengths, whereas for the average coherence times we find an optimum at intermediate coupling strengths. We explain both the lifetime and the coherence results using the standard TLS model, including dipole radiation by phonons and anticorrelated dependence of the energy parameters on environmental fluctuations.