基于超导人工原子的非经典微波场的制备和应用研究

特征转变频率在微波频段的超导量子比特或超导人工原子是一种基于超导约瑟夫森结的参数可控的固态量子器件，它非常适合用来调控非经典微波场。本项目将基于我们以前在这方面的研究工作，着重研究利用超导人工原子产生微波压缩态和双模压缩态。我们的方案和过去利用经典非线性元件例如约瑟夫森参量放大器产生微波压缩态和双模压缩态有着本质区别。我们将利用单个超导人工原子关联辐射激光器产生腔内高压缩度的压缩态或者双模压缩态，突破利用经典非线性元件在腔内制备压缩态-3dB的极限。我们将利用二阶关联函数测量研究微波压缩态或者双模压缩态的统计性质。非经典微波场在量子计算、量子网络和量子精密测量领域可能会有重要应用。

A superconducting qubit or superconducting artificial atom with characterized transition frequency in the microwave range is a kind of controllable solid state quantum device based on superconducting Josephson junction. It is very suitable for quantum controlling of non-classical microwave fields. Based on our previous work in this field, we will concentrate on generation of microwave squeezed states and two-mode squeezed states based on superconducting artificial atoms. There are fundamental differences between our scheme and previous scheme based on classical nonlinear elements like Joesphson Parameteric Amplifers. We will generate high degree microwave squeezed states or two-mode squeezed states inside a cavity based on single superconducting artificial atom correlated emission laser. Our scheme could breakthrough the -3dB limit of squeezed degree in cavity based on classical nonlinear element. We will investigate statistics of microwave squeezed states and two-mode squeezed states. The non-classical microwave fields may have important applications in quantum computing, quantum network and quantum metrology.