# Spin-imbalance-induced transverse magnetization in the Hofstadter-Hubbard model

## TL;DR

This paper explores how population imbalance in the Hofstadter-Hubbard model leads to a novel transverse magnetization phase, revealing complex magnetic behaviors through classical and quantum analyses.

## Contribution

It uncovers a new transverse magnetization phase induced by spin imbalance and provides a comprehensive phase diagram including various magnetic states.

## Key findings

- Discovery of transverse magnetization perpendicular to population imbalance
- Identification of a rich phase diagram with multiple magnetic phases
- Use of classical Monte Carlo and dynamical mean-field methods

## Abstract

The fermionic, time-reversal invariant Hofstadter-Hubbard model with a population difference between the two spin states is investigated. In the strongly interacting regime, where the system can be described by an effective spin model, we find an exotic spin structure by means of classical Monte-Carlo calculations. Remarkably, this spin structure exhibits a transverse net magnetization perpendicular to the magnetization induced by the population imbalance. It is thus inherently different from canted antiferromagnetism. We further investigate effects of quantum fluctuations within the dynamical mean-field approximation and obtain a rich phase diagram including ferromagnetic, anti-ferromagnetic, ferrimagnetic, and transverse magnetization phases.