Electro-spinon in one-dimensional Mott insulator

TL;DR

This paper theoretically investigates the low-energy optical responses of one-dimensional Mott insulators, predicting features like breather modes and analyzing effects of magnetic fields, with implications for experimental detection.

Contribution

It provides an exact analysis of undimerized states and predicts breather mode absorption in dimerized states, offering new insights into optical responses in these systems.

Findings

Exact asymptotic behavior for undimerized state

Prediction of breather mode in dimerized state

Discussion of magnetic field effects

Abstract

The low-energy dynamical optical response of dimerized and undimerized spin liquid states in a one-dimensional charge transfer Mott insulator is theoretically studied. An exact analysis is given for the low-energy asymptotic behavior using conformal field theory for the undimerized state. In the dimerized state, the infrared absorption due to the bound state of two solitons, i.e, the breather mode, is predicted with an accurate estimate for its oscillator strength, offering a way to detect experimentally the excited singlet state. Effects of external magnetic fields are also discussed.