# Chaos in Dirac electron optics: Emergence of a relativistic quantum chimera

## TL;DR

This paper reports a novel quantum scattering phenomenon in 2D Dirac materials where both integrable and chaotic dynamics coexist and are controllable via electrical means, leading to potential spintronic applications.

## Contribution

It introduces the concept of a Dirac quantum chimera, demonstrating simultaneous classical-like chaos and integrability in relativistic quantum systems with spin-dependent effects.

## Key findings

- Coexistence of integrable and chaotic dynamics in Dirac electron scattering.
- Electrical control over quantum fingerprints related to spin states.
- Potential for enhanced spin polarization and spin-selective phenomena.

## Abstract

We uncover a remarkable quantum scattering phenomenon in two-dimensional Dirac material systems where the manifestations of both classically integrable and chaotic dynamics emerge simultaneously and are electrically controllable. The distinct relativistic quantum fingerprints associated with different electron spin states are due to a physical mechanism analogous to chiroptical effect in the presence of degeneracy breaking. The phenomenon mimics a chimera state in classical complex dynamical systems but here in a relativistic quantum setting - henceforth the term "Dirac quantum chimera," associated with which are physical phenomena with potentially significant applications such as enhancement of spin polarization, unusual coexisting quasibound states for distinct spin configurations, and spin selective caustics. Experimental observations of these phenomena are possible through, e.g., optical realizations of ballistic Dirac fermion systems.