Sánchez Martínez Carlos J, Feist Johannes, García-Vidal Francisco J
Departamento de Física Teórica de la Materia Condensada and Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, E-28049 Madrid, Spain.
Institute of High Performance Computing (IHPC), Singapore 138632, Singapore.
Nanophotonics. 2024 Feb 1;13(14):2669-2678. doi: 10.1515/nanoph-2023-0863. eCollection 2024 Jun.
The full information about the interaction between a quantum emitter and an arbitrary electromagnetic environment is encoded in the so-called spectral density. We present an approach for describing such interaction in any coupling regime, providing a Lindblad-like master equation for the emitter dynamics when coupled to a general nanophotonic structure. Our framework is based on the splitting of the spectral density into two terms. On the one hand, a spectral density responsible for the non-Markovian and strong-coupling-based dynamics of the quantum emitter. On the other hand, a residual spectral density including the remaining weak-coupling terms. The former is treated nonperturbatively with a collection of lossy interacting discrete modes whose parameters are determined by a fit to the original spectral density in a frequency region encompassing the quantum emitter transition frequencies. The latter is treated perturbatively under a Markovian approximation. We illustrate the power and validity of our approach through numerical simulations in three different setups, thus offering a variety of scenarios for a full test, including the ultra-strong coupling regime.
量子发射器与任意电磁环境之间相互作用的完整信息编码在所谓的谱密度中。我们提出了一种在任何耦合 regime 下描述这种相互作用的方法，当量子发射器耦合到一般的纳米光子结构时，为发射器动力学提供一个类似林德布拉德的主方程。我们的框架基于将谱密度分解为两项。一方面，一个负责量子发射器非马尔可夫和基于强耦合动力学的谱密度。另一方面，一个残余谱密度，包括其余的弱耦合项。前者通过一组有损相互作用离散模式进行非微扰处理，其参数通过在包含量子发射器跃迁频率的频率区域内对原始谱密度进行拟合来确定。后者在马尔可夫近似下进行微扰处理。我们通过在三种不同设置下的数值模拟来说明我们方法的威力和有效性，从而提供各种场景进行全面测试，包括超强耦合 regime。
