标题： 准粒子引起的驱动超导量子比特的去相干 显示英文标题

标题： Quasiparticle-induced decoherence of a driven superconducting qubit

摘要： 我们发展了一种理论来描述驱动的超导量子比特由准粒子诱导的两种退相干机制。 在第一种机制中，一个存在的准粒子（QP）穿过量子比特的约瑟夫森结的同时吸收了一个量子比特激发和一个（或多个）驱动光子。 在第二种机制中，在非线性吸收过程中，当多个驱动量子被转换成一对新的准粒子时，发生了量子比特跃迁。 这两种机制在那些相干性对无驱动条件下的准粒子不敏感的带隙工程量子比特中仍然可能具有重要意义。 我们的理论确立了微波量子比特操作（如读出和门操作）受准粒子影响的根本限制。 显示英文摘要

摘要： We develop a theory for two quasiparticle-induced decoherence mechanisms of a driven superconducting qubit. In the first mechanism, an existing quasiparticle (QP) tunnels across the qubit's Josephson junction while simultaneously absorbing a qubit excitation and one (or several) photons from the drive. In the second mechanism, a qubit transition occurs during the non-linear absorption process converting multiple drive quanta into a pair of new QPs. Both mechanisms can remain significant in gap engineered qubits whose coherence is insensitive to QPs without the drive. Our theory establishes a fundamental limitation on fidelity of the microwave qubit operations, such as readout and gates, stemming from QPs.