Nanophotonic devices, composed of metals, dielectrics, or semiconductors, enable precise
and high-spatial-resolution manipulation of electromagnetic waves by leveraging diverse …

Becoming invisible at will has fascinated humanity for centuries and in the past decade it
has attracted a great deal of attention owing to the advent of metamaterials. However, state …

Transition radiation is a fundamental process of light emission and occurs whenever a
charged particle moves across an inhomogeneous region. One feature of transition radiation …

We reveal a mechanism to enhance particle-matter interactions by exploiting the pseudo-
Brewster effect of gain materials, presenting an enhancement of at least four orders of …

Localized electromagnetic excitation in the form of toroidal dipoles has recently been
observed in metamaterial systems. The origin of the toroidal dipole lies in the currents …

Impurities usually play an important role in modifying the bulk properties of electronic or
electromagnetic materials. In this work, we demonstrate a way to break this discipline and …

Planar junctions between reactive surface impedances with dual character
(capacitive/inductive) can sustain line waves localized both in-plane and out-of-plane …

Causality—the principle stating that the output of a system cannot temporally precede the
input—is a universal property of nature. Here, we show that analogous input-output relations …

By directly incorporating a sub-wavelength amplifier chip into the spoof plasmonic resonator,
the quality (Q) factor of the original passive resonator has been significantly increased by …

Parity-time-symmetric (PT-symmetric) metasurfaces exhibit a plethora of fascinating
exceptional-point-induced phenomena, including unidirectional negative refraction and …