Quantum liquid with strong orbital fluctuations: the case of a pyroxene family

TL;DR

This paper investigates the magnetic and orbital properties of pyroxene family Mott insulators, highlighting conditions for orbital liberation and resulting changes in excitation spectra.

Contribution

It provides a theoretical analysis of orbital fluctuations and excitation spectra in pyroxene Mott insulators, revealing conditions for orbital liberation.

Findings

Orbital degrees of freedom can become liberated under certain conditions.

Spectral weight shifts to lower energies when orbitals are liberated.

Excitation spectra become dispersive with orbital liberation.

Abstract

We discuss quasi one-dimensional magnetic Mott insulators of the pyroxene family where spin and orbital degrees of freedom remain tightly bound. We analyze their excitation spectrum and outline the conditions under which the orbital degrees of freedom become liberated so that the excitations become dispersive and the spectral weight shifts to energies much smaller than the exchange integral.