基于多能级超导量子电路的相关非线性光学效应和量子无损测量

Based on the new designed four level superconducting quantum circuits and cross Kerr effect (Phys. Rev. A84 (2011) 012329), it is possible to produce different nonlinear optical effects by using this superconducting artificial atom coupling with microwave-transmission line cavity (or cavities) and interacting with light. The goal of this proposal is to deal with some related nonlinear optical effects based on the suitalbe designes for the circuits and optical interactions due to previous researches and quantum non-demolition measurements based on the multi-level and cross Kerr effect. The nonlinear optical effects to be studied include two-mode entangled laser, two-mode squeezed state effect,and as well as the quantum no-ndemolition measurements based on the superconducting multi-level articial atoms. All these effects were realized in real atom-cavity systems. However, the realization of these effects in the superconducting circuits willl meet the requirments of on-chip and on-demand, because the strong coupling between the superconducting artifical atom and the cavity fields can be realized by manufacturelly locating an artifical atom at the maximum position of the cavity field. It is expected that the researches on various nonlinear optical effects can be extended to the system of superconducting quamtum circuits, and open a new way for the applications of superconducting articial atom in the intergrated optics and optical quantum measurements, and as well as in quantum information and quantum technology.

非线性光学效应在量子信息和量子测量方面有重要的应用。本项目是基于我们设计的新型四能级超导量子电路和交叉非线性Kerr效应（Phys.Rev.A 84 （2011）012329），将这种超导人造原子通过与微波传输线腔耦合和与光场不同模式的相互作用下，来研究由此产生的相关非线性光学效应，比如多光场作用下的双模纠缠激光；非线性相互作用下产生的两模光子压缩态效应，以及与此相关的量子无损测量。这些效应原本在实际原子中都有产生，而超导量子电路则可以实行On-chip、on-demand的要求，由于可以将超导人造原子置于光学腔的最大场强处，易于在腔中实现强耦合，以达到所设计和期望的量子光学效应。而相关联的非线性光学效应则可在超导量子电路和相关集成电路环境下来实现量子信息传递、存储、和量子态的测量。同时，本研究从长远的角度，可产生与此相关的基于超导量子电路的非线性光学理论和实验,及在量子信息等领域的应用。

超导量子电路在量子信息处理和量子计算中有重要应用。因此，近年来国际上这方面的研究成为热点方向之一。我们研究了超导量子电路中的非线性光学特性，EIT，电磁感应透明与Autler-Townes分裂之间跃迁的缀饰态实现；四能级电磁感应透明和Autler–Townes分裂；量子Zeno效应；单个人造原子的非线性光学；相位和频率控制的非线性光学。利用共振荧光谱分析确定人造原子中的量子态分布等等。这些研究在量子控制和量子计算上有重要的应用。作为研究的扩展我们还研究了腔中的冷原子，光学晶格中费米子的自旋与轨道相互作用；耗散或非Markov环境下量子信息处理与量子动力学的若干问题。研究总体上按计划执行，执行情况好。