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 …

This is a review on theoretical and experimental studies on dielectric microcavities, which
play a significant role in fundamental and applied research. The basic concepts and theories …

Optical whispering gallery modes (WGMs) derive their name from a famous acoustic
phenomenon of guiding a wave by a curved boundary observed nearly a century ago. This …

We summarize the properties of eigenvalues and eigenfunctions of the Laplace operator in
bounded Euclidean domains with Dirichlet, Neumann, or Robin boundary condition. We …

We present spectroscopic observation of an exceptional point or the transition point between
mode crossing and avoided mode crossing of neighboring quasieigenmodes in a chaotic …

A boundary element method based on a Green function technique is introduced to compute
resonances with intermediate lifetimes in quasi-two-dimensional dielectric cavities. It can be …

We report unidirectional emission from lasing in In 0.09 Ga 0.91 N/In 0.01 Ga 0.99 N multiple-
quantum-well spiral micropillars. Our imaging technique shows that the maximum emission …

We study the formation of long-lived states near avoided resonance crossings in open
systems. For three different optical microcavities (rectangle, ellipse, and semistadium) we …

A semiclassical theory of single and multimode lasing is derived for open complex or
random media using a self-consistent linear response formulation. Unlike standard …

It is numerically shown that the Petermann excess noise factor diverges to infinity at an
exceptional point (EP) found near an avoided resonance crossing in a stadium-shaped …