Topological phases and bulk-edge correspondence of magnetized cold plasmas

TL;DR

This paper systematically maps topological phases in cold magnetized plasmas, revealing conditions for edge modes at interfaces, which could impact space and laboratory plasma applications.

Contribution

It provides the first comprehensive classification of topological phases and bulk-edge correspondence in cold magnetized plasmas, identifying specific phase transitions and edge mode conditions.

Findings

Identifies 10 topological phases in plasma parameter space.

Establishes the bulk-edge correspondence and conditions for edge modes.

Demonstrates edge modes on various plasma interfaces.

Abstract

Plasmas have been recently studied as topological materials. However, a comprehensive picture of topological phases and topological phase transitions in cold magnetized plasmas is still missing. Here we systematically map out all the topological phases and establish the bulk-edge correspondence in cold magnetized plasmas. We find that for the linear eigenmodes, there are 10 topological phases in the parameter space of density $n$, magnetic field $B$, and parallel wavenumber $k_{z}$, separated by the surfaces of Langmuir wave-L wave resonance, Langmuir wave-cyclotron wave resonance, and zero magnetic field. For fixed $B$ and $k_{z}$, only the phase transition at the Langmuir wave-cyclotron wave resonance corresponds to edge modes. A sufficient and necessary condition for the existence of this type of edge modes is given and verified by numerical solutions. We demonstrate that edge modes exist not only on a plasma-vacuum interface but also on more general plasma-plasma interfaces. This finding broadens the possible applications of these exotic excitations in space and laboratory plasmas.