As a fundamental optical approach to interferometry, Sagnac interference has been widely
used for reflection manipulation, precision measurements, and spectral engineering in …

The topological properties of an object, associated with an integer called the topological
invariant, are global features that cannot change continuously but only through abrupt …

Exceptional points are spectral singularities in open quantum and wave systems that exhibit
a strong spectral response to perturbations. This feature can be exploited for a new …

Non-Hermitian degeneracies, also known as exceptional points, have recently emerged as
a new way to engineer the response of open physical systems, that is, those that interact …

Exceptional points (EPs) are special spectral degeneracies of non-Hermitian Hamiltonians
that govern the dynamics of open systems. At an EP, two or more eigenvalues, and the …

Gyroscopes are essential to many diverse applications associated with navigation,
positioning and inertial sensing. In general, most optical gyroscopes rely on the Sagnac …

Optical gyroscopes are among the most accurate rotation measuring devices and are widely
used for navigation and accurate pointing. Since the advent of photonic integrated …

Several types of sensors used in physics are based on the detection of splittings of resonant
frequencies or energy levels. We propose here to operate such sensors at so-called …

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 …

A general theory of sensors based on the detection of splittings of resonant frequencies or
energy levels operating at so-called exceptional points is presented. Exploiting the complex …