Cross-Kerr-effect induced by coupled Josephson qubits in circuit quantum electrodynamics
Cross-Kerr-effect induced by coupled Josephson qubits in circuit quantum electrodynamics
复制标题
电路量子电动力学中耦合约瑟夫森量子位引起的交叉克尔效应
DOI：
10.1103/physreva.84.012329
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发表时间：
2011-07-25
影响因子：
2.9
通讯作者：
Chen, You-Ling
中科院分区：
文献类型：
--
作者：
Hu, Yong;Ge, Guo-Qin;Chen, You-Ling
我们提出了一个方案，实现交叉克尔非线性之间的两个超导传输线谐振器（TLR）通过它们的相互作用与耦合器构造的两个超导transmon量子比特通过超导量子干涉器件相互连接。当适当地驱动时，耦合器可以在两个TLR之间引起非常强的交叉相位调制（XPM），这是由于其$N$型能级结构和随之而来的在其最低状态下的电磁感应透明性。我们设计的灵活性可以导致各种TLR间耦合配置。得到的交叉克尔系数足够大，允许许多重要的量子操作中，只有很少的光子参与。我们进一步表明，该计划是非常强大的对波动的固态量子电路。我们的数值计算意味着，吸收和色散的TLR的耦合器的退相干产生的是非常小的建议XPM强度相比。
We propose a scheme for implementing cross-Kerr nonlinearity between two superconducting transmission line resonators (TLRs) via their interactions with a coupler constructed by two superconducting transmon qubits connected to each other through a superconducting quantum interference device. When suitably driven, the coupler can induce very strong cross phase modulation (XPM) between the two TLRs due to its $N$-type level structure and the consequent electromagnetically induced transparency in its lowest states. The flexibility of our design can lead to various inter-TLR coupling configurations. The obtained cross-Kerr coefficient is large enough to allow many important quantum operations in which only few photons are involved. We further show that this scheme is very robust against fluctuations in solid-state quantum circuits. Our numerical calculations imply that the absorption and the dispersion of the TLRs resulting from the decoherence of the coupler are very small compared with the proposed XPM strength.