Transport of Neutral Optical Excitations Using Electric Fields

• Main Authors: Ovidiu Cotleţ, Falko Pientka, Richard Schmidt, Gergely Zarand, Eugene Demler, Atac Imamoglu
• Format: Article
• Language: English
• Published: American Physical Society 2019-10-01
• Series: Physical Review X
• Online Access: http://doi.org/10.1103/PhysRevX.9.041019

Mobile quantum impurities interacting with a fermionic bath form quasiparticles known as Fermi polarons. We demonstrate that a force applied to the bath particles can generate a drag force of similar magnitude acting on the impurities, realizing a novel, nonperturbative Coulomb drag effect. To prove this, we calculate the fully self-consistent, frequency-dependent transconductivity at zero temperature in the Baym-Kadanoff conserving approximation. We apply our theory to excitons and exciton polaritons interacting with a bath of charge carriers in a doped semiconductor embedded in a microcavity. In external electric and magnetic fields, the drag effect enables electrical control of excitons and may pave the way for the implementation of gauge fields for excitons and polaritons. Moreover, a reciprocal effect may facilitate optical manipulation of electron transport. Our findings establish transport measurements as a novel, powerful tool for probing the many-body physics of mobile quantum impurities.