Lasers are the pillars of modern optics and sensing. Microlasers based on whispering-
gallery modes (WGMs) are miniature in size and have excellent lasing characteristics …

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 …

Harnessing parity–time symmetry with balanced gain and loss profiles has created a variety
of opportunities in electronics from wireless energy transfer to telemetry sensing and …

Optical monitoring of the position and alignment of objects with a precision of only a few
nanometres is key in applications such as smart manufacturing and force sensing …

Recently, non-Hermitian Hamiltonians have gained a lot of interest, especially in optics and
electronics. In particular, the existence of real eigenvalues of non-Hermitian systems has …

The realization of higher-order exceptional points (HOEPs) can lead to orders of magnitude
enhancement in light-matter interactions beyond the current fundamental limits …

We propose a multiband metamaterial absorber consisting of silicon brick array on metal
substrate in infrared range. Using the regular hexagon array of silicon bricks, the absorption …

We present a quasinormal-mode (QNM) theory for coupled loss and gain resonators
working in the vicinity of an exceptional point. Assuming linear media, which can be fully …

Optical microcavities offer a promising platform for highly efficient light–matter interactions.
Recently, the combination of microresonators and 2D materials in the nanoscale has further …

We demonstrate a fundamental breakdown of the photonic spontaneous emission (SE)
formula derived from Fermi's golden rule, in absorptive and amplifying media, where one …