Rotational Resonances and Regge Trajectories in Lightly Doped Antiferromagnets

TL;DR

This paper numerically uncovers long-lived rotational resonances in lightly doped antiferromagnets, revealing the microscopic structure of spinon-chargon bound states and proposing multi-photon ARPES as a tool to detect these features.

Contribution

It introduces the first direct numerical evidence of rotational resonances indicating spinon-chargon bound states and connects their energy dependence to super-exchange coupling, proposing experimental detection methods.

Findings

Identification of long-lived rotational resonances in low doping regimes.

Linear dependence of rotational energy on super-exchange coupling.

Proposal of multi-photon ARPES to observe these resonances.

Abstract

Understanding the nature of charge carriers in doped Mott insulators holds the key to unravelling puzzling properties of strongly correlated electron systems, including cuprate superconductors. Several theoretical models suggested that dopants can be understood as bound states of partons, the analogues of quarks in high-energy physics. However, direct signatures of spinon-chargon bound states are lacking, both in experiment and theory. Here we numerically identify long-lived rotational resonances at low doping, which directly reveal the microscopic structure of spinon-chargon bound states. Similar to Regge trajectories reflecting the quark structure of mesons, we establish a linear dependence of the rotational energy on the super-exchange coupling. Rotational excitations are strongly suppressed in standard angle-resolved photo-emission (ARPES) spectra, but we propose a multi-photon rotational extension of ARPES where they have strong spectral weight. Our findings suggest that multi-photon spectroscopy experiments should provide new insights into emergent universal features of strongly correlated electron systems.