由原子薄半导体中的耗散光物质耦合诱导的负质量激子极化激元。

Negative-mass exciton polaritons induced by dissipative light-matter coupling in an atomically thin semiconductor.

机构信息

ARC Centre of Excellence in Future Low-Energy Electronics Technologies and Department of Quantum Science and Technology, Research School of Physics, The Australian National University, Canberra, ACT, 2601, Australia.

Department of Materials Science and Engineering, Monash University, Clayton, Victoria, 3800, Australia.

出版信息

Nat Commun. 2023 Feb 23;14(1):1026. doi: 10.1038/s41467-023-36618-6.

DOI:10.1038/s41467-023-36618-6

PMID:36823076

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC9950362/

Abstract

Dispersion engineering is a powerful and versatile tool that can vary the speed of light signals and induce negative-mass effects in the dynamics of particles and quasiparticles. Here, we show that dissipative coupling between bound electron-hole pairs (excitons) and photons in an optical microcavity can lead to the formation of exciton polaritons with an inverted dispersion of the lower polariton branch and hence, a negative mass. We perform direct measurements of the anomalous dispersion in atomically thin (monolayer) WS crystals embedded in planar microcavities and demonstrate that the propagation direction of the negative-mass polaritons is opposite to their momentum. Our study introduces the concept of non-Hermitian dispersion engineering for exciton polaritons and opens a pathway for realising new phases of quantum matter in a solid state.

摘要

色散工程是一种强大而多功能的工具，可以改变光信号的速度，并在粒子和准粒子的动力学中诱导负质量效应。在这里，我们表明，在光学微腔中束缚电子-空穴对（激子）和光子之间的耗散耦合可以导致形成具有下极化分支的反转色散的激子极化激元，从而产生负质量。我们对嵌入在平面微腔中的原子薄（单层）WS 晶体中的激子极化激元的反常色散进行了直接测量，并证明了负质量极化激元的传播方向与其动量相反。我们的研究为激子极化激元的非厄米色散工程引入了新概念，并为在固态中实现新的量子物质相开辟了道路。