Casimir Force Phase Transitions in the Graphene Family

TL;DR

This paper explores how the Casimir force between graphene family materials can undergo phase transitions influenced by Dirac physics, spin-orbit coupling, and external fields, revealing tunable and potentially repulsive quantum interactions.

Contribution

It introduces the concept of Casimir force phase transitions in the graphene family, highlighting the role of topological properties and external controls in modulating quantum forces.

Findings

Casimir force exhibits different power law decay behaviors.

Repulsive and quantized Casimir interactions are possible.

Force characteristics depend on physical constants and external fields.

Abstract

The Casimir force is a universal interaction induced by electromagnetic quantum fluctuations between any types of objects. The expansion of the graphene family by adding silicene, germanene, and stanene, 2D allotropes of Si, Ge, and Sn, lands itself as a platform to probe Dirac-like physics in honeycomb staggered systems in such a ubiquitous interaction. We discover Casimir force phase transitions between these staggered 2D materials induced by the complex interplay between Dirac physics, spin-orbit coupling, and externally applied fields. In particular, we find that the interaction energy experiences different power law distance decays, magnitudes, and dependences on characteristic physical constants. Furthermore, due to the topological properties of these materials, repulsive and quantized Casimir interactions become possible.