# Unusual Frequency of Quantum Oscillations in Strongly Particle-Hole Asymmetric Insulators

## TL;DR

This paper reveals that in strongly particle-hole asymmetric insulators, quantum oscillations exhibit frequency variations and differences between magnetization and density of states oscillations, contrasting with symmetric insulators.

## Contribution

It demonstrates that particle-hole asymmetry causes distinct frequencies in quantum oscillations and their temperature dependence, expanding understanding of insulator behavior.

## Key findings

- Quantum oscillation frequencies differ in asymmetric insulators.
- Oscillation frequency in density of states varies with temperature.
- Robustness of frequency in symmetric insulators does not hold in asymmetric cases.

## Abstract

Quantum oscillations, conventionally thought to be a metallic property, have recently been shown to arise in certain kinds of insulators, with properties very different from those in metals. All departures from the canonical behavior found so far arise only in the amplitude and the phase but not in the frequency. Here I show that such robustness in the behavior of the frequency is only valid for a particle-hole symmetric insulator; in a strongly particle-hole asymmetric insulator, de Haas-van Alphen oscillations (oscillations in magnetization and susceptibility) and Shubnikov-de Haas oscillations (oscillations in the density of states) exhibit different frequencies, with the frequency of the latter changing with temperature. I demonstrate these effects with numerical calculations on a lattice model, and provide a theory to account for the unusual behavior.