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 …

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 …

A short résumé is given about the nature of exceptional points (EPs) followed by discussions
about their ubiquitous occurrence in a great variety of physical problems. EPs feature in …

Parity-time (PT) symmetric periodic structures, near the spontaneous PT-symmetry breaking
point, can act as unidirectional invisible media. In this regime, the reflection from one end is …

One of the fundamental axioms of quantum mechanics is associated with the Hermiticity of
physical observables. In the case of the Hamiltonian operator, this requirement not only …

One of the challenges of the modern photonics is to develop all‐optical devices enabling
increased speed and energy efficiency for transmitting and processing information on an …

Mutually coupled modes of a pair of active LRC circuits, one with amplification and another
with an equivalent amount of attenuation, provide an experimental realization of a wide …

In a recent work, YD Chong [Phys. Rev. Lett. 105, 053901 (2010)] 0031-9007
10.1103/PhysRevLett. 105.053901 proposed the idea of a coherent perfect absorber (CPA) …

We show that nonlinear optical structures involving a balanced gain-loss profile can act as
unidirectional optical valves. This is made possible by exploiting the interplay between the …

Dissipation in mechanics, optics, acoustics, and electronic circuits is nowadays recognized
to be not always detrimental but can be exploited to achieve non-Hermitian topological …