Non-Hermitian optics is a burgeoning field at the intersection of quantum physics,
electrodynamics, and nanophotonics. It provides a new perspective of the role of gain and …

A review is given on the foundations and applications of non-Hermitian classical and
quantum physics. First, key theorems and central concepts in non-Hermitian linear algebra …

Exploiting the interplay between gain, loss and the coupling strength between different
optical components creates a variety of new opportunities in photonics to generate, control …

BACKGROUND Singularities are critical points for which the behavior of a mathematical
model governing a physical system is of a fundamentally different nature compared to the …

In recent years, notions drawn from non-Hermitian physics and parity–time (PT) symmetry
have attracted considerable attention. In particular, the realization that the interplay between …

Nearly one century after the birth of quantum mechanics, parity–time symmetry is
revolutionizing and extending quantum theories to include a unique family of non-Hermitian …

In the past few years, concepts from non-Hermitian (NH) physics, originally developed within
the context of quantum field theories, have been successfully deployed over a wide range of …

Recent progress on nonlinear properties of parity-time (PT)-symmetric systems is
comprehensively reviewed in this article. PT symmetry started out in non-Hermitian quantum …

The bulk-boundary correspondence is crucial to topological insulators. It associates the
existence of boundary states (with zero energy and possessing chiral or helical properties) …

Optical systems combining balanced loss and gain provide a unique platform to implement
classical analogues of quantum systems described by non-Hermitian parity–time (PT) …