Fermi arc reconstruction in synthetic photonic lattice

TL;DR

This paper demonstrates Fermi arc reconstruction in a synthetic photonic lattice that emulates Weyl semimetals, revealing phase transitions and confirming theoretical predictions through numerical simulations.

Contribution

It introduces a 1D dielectric trilayer grating system that emulates 3D Weyl semimetals and observes Fermi arc reconstruction experimentally.

Findings

Phase transition between Weyl semimetal and Chern insulator at telecom wavelength

Observation of Fermi arc reconstruction between two Weyl semimetals

System emulates 3D topological phases in a 1D photonic structure

Abstract

The chiral surface states of Weyl semimetals have an open Fermi surface called Fermi arc. At the interface between two Weyl semimetals, these Fermi arcs are predicted to hybridize and alter their connectivity. In this letter, we numerically study a one-dimensional (1D) dielectric trilayer grating where the relative displacements between adjacent layers play the role of two synthetic momenta. The lattice emulates 3D crystals without time-reversal symmetry, including Weyl semimetal, nodal line semimetal, and Chern insulator. Besides showing the phase transition between Weyl semimetal and Chern insulator at telecom wavelength, this system allows us to observe the Fermi arc reconstruction between two Weyl semimetals, confirming the theoretical predictions.