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 …

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 …

This chapter introduces the basic ideas of P T-symmetric systems. It begins with a brief
discussion of closed (isolated) and open (non-isolated) systems and explains that P T …

Structured light provides an additional degree of freedom for modern optics and practical
applications. The effective generation of orbital angular momentum (OAM) lasing, especially …

Sensing an incoming signal is typically associated with absorbing a portion of its energy,
inherently perturbing the measurement and creating reflections and shadows. Here, in …

The scattering of electromagnetic waves lies at the heart of most experimental techniques
over nearly the entire electromagnetic spectrum, ranging from radio waves to optics and x …

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 …

Lasing, light amplification by stimulated emission of radiation, is a key attribute for many
important applications in optical communications, medicine and defence. Conversely, anti …

Effective manipulation of cavity resonant modes is crucial for emission control in laser
physics and applications. Using the concept of parity-time symmetry to exploit the interplay …