Wang Zibo, Khatiwada Pawan, Wang Dan, Mirza Imran M
Opt Express. 2022 Mar 14;30(6):9360-9379. doi: 10.1364/OE.449275.
We theoretically study the conditions under which two laser fields can undergo Coherent Perfect Absorption (CPA) when shined on a single-mode bi-directional optical cavity coupled with two two-level quantum emitters (natural atoms, artificial atoms, quantum dots, qubits, etc.). In addition to being indirectly coupled through the cavity-mediated field, in our Tavis-Cummings model, the two quantum emitters (QEs) are allowed to interact directly via the dipole-dipole interaction (DDI). Under the mean-field approximation and low-excitation assumption, in this work, we particularly focus on the impact of DDI on the existence of CPA in the presence of decoherence mechanisms (spontaneous emission from the QEs and the leakage of photons from the cavity walls). We also present a dressed-state analysis of the problem to discuss the underlying physics related to the allowed polariton state transitions in the Jaynes-Tavis-Cummings ladder. As a key result, we find that in the strong-coupling regime of cavity quantum electrodynamics, the strong DDI and the emitter-cavity detuning can act together to achieve the CPA at two laser frequencies tunable by the inter-atomic separation which are not possible to attain with a single QE in the presence of detuning. Our CPA results are potentially applicable in building quantum memories that are an essential component in long-distance quantum networking.
我们从理论上研究了在与两个二能级量子发射器（自然原子、人造原子、量子点、量子比特等）耦合的单模双向光学腔上照射两个激光场时，它们能够发生相干完美吸收（CPA）的条件。在我们的塔维斯 - 卡明斯模型中，除了通过腔介导的场间接耦合外，两个量子发射器（QEs）还被允许通过偶极 - 偶极相互作用（DDI）直接相互作用。在平均场近似和低激发假设下，在这项工作中，我们特别关注在存在退相干机制（QEs的自发辐射和光子从腔壁的泄漏）的情况下，DDI对CPA存在的影响。我们还对该问题进行了缀饰态分析，以讨论与杰恩斯 - 塔维斯 - 卡明斯阶梯中允许的极化激元态跃迁相关的潜在物理机制。作为一个关键结果，我们发现，在腔量子电动力学的强耦合 regime 中，强DDI和发射器 - 腔失谐可以共同作用，在两个由原子间距离可调的激光频率处实现CPA，而在存在失谐的情况下，单个QE是无法达到这一点的。我们的CPA结果可能适用于构建量子存储器，而量子存储器是长距离量子网络中的一个重要组成部分。
