Finite Temperature Effects in One-dimensional Mott-Hubbard Insulator: Angle-Resolved Photoemission Study of Na_{0.96}V_{2}O_{5}

TL;DR

This study investigates how finite temperature influences the electronic structure of a 1D Mott-Hubbard insulator Na_{0.96}V_{2}O_{5} using angle-resolved photoemission and theoretical modeling, revealing temperature-dependent spectral changes.

Contribution

It combines experimental ARPES data with exact diagonalization calculations of the 1D t-J model to analyze finite temperature effects in a Mott insulator, highlighting the role of the spinon Fermi surface.

Findings

Strong temperature dependence of V 3d Hubbard band spectra

Good agreement between experimental data and theoretical spectral functions

Finite temperature effects linked to the spinon Fermi surface

Abstract

We have made an angle-resolved photoemission study of a one-dimensional (1D) Mott-Hubbard insulator Na_{0.96}V_{2}O_{5} and found that the spectra of the V 3d lower Hubbard band are strongly dependent on the temperature. We have calculated the one-particle spectral function of the one-dimensional t-J model at finite temperatures by exact diagonalization and compared them with the experimental results. Good overall agreement is obtained between experiment and theory. The strong finite temperature effects are discussed in terms of the existence of the ``Fermi surface'' of the spinon band.