Fermion Casimir effect and magnetic Larkin-Ovchinnikov phases

TL;DR

This study investigates how magnetic fields influence the fermionic Casimir effect in a quasi-1D system, revealing novel phase transitions and force discontinuities due to boundary interactions.

Contribution

It introduces a new understanding of magnetic field effects on the Casimir effect, showing complex ground state changes and phase transitions in fermionic systems.

Findings

Casimir force exhibits jumps at phase transition points

Magnetic fields induce inhomogeneous ground states with different node counts

First-order phase transitions occur between distinct ground states

Abstract

This paper explores how magnetic fields affect the Casimir effect within the context of a simple quasi-1D interacting fermionic system. A novel phenomenon emerges, resulting from the interaction between external magnetic fields and boundary conditions, which alters the ground state in complex ways and leads to first-order phase transitions among various ground states, specifically inhomogeneous solutions with differing node counts. We calculate the Casimir force, which exhibits discontinuities (jumps) at the transition points between the different ground states.