Trion liquid and its photoemission signatures

TL;DR

This paper investigates the formation of a trion liquid in doped low-dimensional semiconductors with strong electron-hole interactions, identifying its ARPES signatures near phase boundaries using advanced numerical methods.

Contribution

It introduces the concept of a trion liquid in doped semiconductors and analyzes its photoemission signatures with a novel microscopic model and MPS calculations.

Findings

Trion liquid forms near the phase boundary between insulator states.

Partially occupied trion band causes in-gap ARPES features.

In-gap spectral weight vanishes at the Fermi energy.

Abstract

We study the formation of a trion liquid in doped low-dimensional semiconductors with strong electron-hole interactions and analyze its signatures in angle-resolved photoemission spectroscopy (ARPES). We show that this strongly correlated state of matter forms naturally in the vicinity of the phase boundary between a normal band insulator and an excitonic insulator upon doping. By studying the photoemission spectrum, we show that a partially occupied trion band gives rise to an in-gap feature in the ARPES spectrum with vanishing spectral weight at the Fermi energy. We demonstrate our findings using a 1D microscopic model employing exact, unbiased, matrix product state (MPS)-based calculations.