Spectral properties of the 2D Holstein t-J model

TL;DR

This paper introduces a computational approach combining Lanczos, KPM, and MEM to analyze charge and spin excitations, polaron formation, and optical conductivity in the 2D Holstein t-J model with full quantum phonon treatment.

Contribution

It presents a novel computational method for calculating spectral functions and optical conductivity in the 2D Holstein t-J model, including quantum phonon effects.

Findings

Calculated charge and spin excitations across various electron-phonon couplings.

Analyzed polaron band formation through the hole spectral function.

Provided the first results for optical conductivity in this model.

Abstract

Employing the Lanczos algorithm in combination with a kernel polynomial moment expansion (KPM) and the maximum entropy method (MEM), we show a way of calculating charge and spin excitations in the Holstein t-J model, including the full quantum nature of phonons. To analyze polaron band formation we evaluate the hole spectral function for a wide range of electron-phonon coupling strengths. For the first time, we present results for the optical conductivity of the 2D Holstein t-J model.