论文标题
二维半导体和塔维斯 - 卡明模型中的激子 - 波龙
Exciton-polarons in two-dimensional semiconductors and the Tavis-Cummings model
论文作者
论文摘要
二维电子或孔系统的基本光激发已被鉴定为激子 - 富尔米 - 棕榈。然而，激子的结合状态与电子（称为TRION）和激子 - 核酸元之间的联系是正在进行的争论的主题。在这里，我们使用与量子光学的Tavis-cummings模型的类比，以表明激子 - 核酸可以理解为混合式准粒子 - 在不受干扰的费米海中裸露的激子的连贯叠加，以及许多TRIONS的明亮集体激励。该类比是有效的，在雪佛兰Ansatz提供了对激子动态筛选的良好描述，并且前提是费米能量比Trion结合能小得多。我们预计我们的结果将带来新的见解，可以帮助解释二维半导体的吸收和发射光谱之间的显着差异。
The elementary optical excitations of a two-dimensional electron or hole system have been identified as exciton-Fermi-polarons. Nevertheless, the connection between the bound state of an exciton and an electron, termed trion, and exciton-polarons is subject of ongoing debate. Here, we use an analogy to the Tavis-Cummings model of quantum optics to show that an exciton-polaron can be understood as a hybrid quasiparticle -- a coherent superposition of a bare exciton in an unperturbed Fermi sea and a bright collective excitation of many trions. The analogy is valid to the extent that the Chevy Ansatz provides a good description of dynamical screening of excitons and provided the Fermi energy is much smaller than the trion binding energy. We anticipate our results to bring new insight that could help to explain the striking differences between absorption and emission spectra of two-dimensional semiconductors.
