Quasiparticle Relaxation of Superconducting Qubits in the Presence of Flux
Quasiparticle Relaxation of Superconducting Qubits in the Presence of Flux
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DOI：
10.1103/physrevlett.106.077002
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发表时间：
2011-02-16
影响因子：
8.6
通讯作者：
Glazman, L. I.
中科院分区：
文献类型：
--
作者：
Catelani, G.;Koch, J.;Glazman, L. I.
穿过约瑟夫森结的准粒子隧穿为超导量子比特态的寿命设定了极限。我们开发了一个一般的理论，相应的衰变率的量子比特控制的磁通量。通量影响准粒子隧穿振幅，从而使衰变率通量依赖。该理论适用于任意准粒子分布。它提供了在实际重要的量子电路的速率估计，也提供了一种新的方法来测量约瑟夫森结的相位相关导纳。
Quasiparticle tunneling across a Josephson junction sets a limit for the lifetime of a superconducting qubit state. We develop a general theory of the corresponding decay rate in a qubit controlled by a magnetic flux. The flux affects quasiparticles tunneling amplitudes, thus making the decay rate flux-dependent. The theory is applicable for an arbitrary quasiparticle distribution. It provides estimates for the rates in practically important quantum circuits and also offers a new way of measuring the phase-dependent admittance of a Josephson junction.