Exceptional points (EPs) arising in non-Hermitian systems have led to a variety of intriguing
wave phenomena, and have been attracting increased interest in various physical platforms …

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 …

Dissipation is a general feature of non-Hermitian systems. But rather than being an
unavoidable nuisance, non-Hermiticity can be precisely controlled and hence used for …

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 …

Topological photonics seeks to control the behaviour of the light through the design of
protected topological modes in photonic structures. While this approach originated from …

It is generally assumed that a Hamiltonian for a physically acceptable quantum system (one
that has a positive-definite spectrum and obeys the requirement of unitarity) must be …