# Floquet Spinor Bose Gases

## TL;DR

This paper explores how a high-frequency periodic drive can induce novel phases and behaviors in spinor Bose-Einstein condensates, revealing rich phase transitions and metastable states.

## Contribution

It introduces a Floquet engineering approach to spinor BECs, demonstrating new stationary states and metastable regions due to external periodic driving.

## Key findings

- Unconventional stationary states in ferromagnetic condensates
- Rich continuous phase transitions observed
- Metastable regions with unusual excitations and hysteresis

## Abstract

We introduce a Floquet spinor Bose-Einstein condensate induced by a periodically driven quadratic Zeeman coupling whose frequency is larger than any other energy scales. By examining a spin-1 system available in ultracold atomic gases, we demonstrate that such an external driving field has great effect on the condensate through emergence of a unique spin-exchange interaction. We uncover that the ferromagnetic condensate has several unconventional stationary states and thus exhibits rich continuous phase transitions. On the other hand, the antiferromagnetic condensate is found to possess a nontrivial metastable region, which supports unusual elementary excitations and hysteresis phenomena.