Comment on "Anomalous Edge State in a Non-Hermitian Lattice"

TL;DR

This paper critically examines a previous work on non-Hermitian lattices, challenging its key conclusions by arguing that the fractional winding number is fictitious, finite-size effects influence results, and the breakdown of bulk-boundary correspondence is not due to defects.

Contribution

It provides a critical analysis disputing the validity of the fractional winding number and the explanations for finite-size effects and bulk-boundary correspondence breakdown in the original study.

Findings

The fractional winding number is considered fictitious.

Finite-size effects influence the results in the original study.

The breakdown of bulk-boundary correspondence is not due to defects.

Abstract

In this comment, we criticize three main conclusions of the letter\cite{Lee2016}. We show that the concept of fractional winding number(FWN) is factitious, Lee's conclusions on Fig. 3 are finite-size effect and the breakdown of bulk-boundary correspondence (BBBC) cannot be explained by "defective".