论文标题
放大的最终量子限制：镜子前的一个原子
Ultimate quantum limit for amplification: a single atom in front of a mirror
论文作者
论文摘要
我们研究了三种类型的放大过程，用于在一维半少数波导的末端附近的原子耦合到原子。我们考虑两个设置，其中驱动器以三级原子的裸露或穿着基础创建人口倒置，而一个设置是由于驱动的两级原子中的高阶过程所致。在所有情况下，波导的末端都是光的镜子。我们发现，与开放式波导中的相同设置相比，这可以通过两种方式增强扩增。首先，镜像迫使所有从原子输出到一个方向行驶，而不是分为两个输出通道。其次，由于镜子引起的干扰能够调整原子中不同过渡的松弛率比以增加种群反转。由于这些因素，我们量化了扩增的增强，并表明可以在超导量子电路实验中为标准参数证明它。
We investigate three types of amplification processes for light fields coupling to an atom near the end of a one-dimensional semi-infinite waveguide. We consider two setups where a drive creates population inversion in the bare or dressed basis of a three-level atom and one setup where the amplification is due to higher-order processes in a driven two-level atom. In all cases, the end of the waveguide acts as a mirror for the light. We find that this enhances the amplification in two ways compared to the same setups in an open waveguide. Firstly, the mirror forces all output from the atom to travel in one direction instead of being split up into two output channels. Secondly, interference due to the mirror enables tuning of the ratio of relaxation rates for different transitions in the atom to increase population inversion. We quantify the enhancement in amplification due to these factors and show that it can be demonstrated for standard parameters in experiments with superconducting quantum circuits.
