Optical logic operations lie at the heart of optical computing, and they enable many
applications such as ultrahigh-speed information processing. However, the reported optical …

In the past decade, the concept of parity-time $(\mathcal {PT}) $ symmetry, originally
introduced in non-Hermitian extensions of quantum mechanical theories, has come into …

Exceptional points (EPs) are singularities that arise in non-Hermitian physics. Current
research efforts focus only on systems supporting isolated EPs characterized by increased …

Kramers-Kronig (KK) relation between the dispersion and absorption responses of a signal
field can be mapped from the frequency domain into the space domain via the dipole-dipole …

The satisfactory realization of a metamaterial (MM) absorber simultaneously occupying low-
profile, wide-bandwidth, particularly and fully angular stability characteristics is a long-term …

Abstract Spatial Kramers–Kronig (KK) medium provides a new platform to achieve
omnidirectionally reflectionless absorption without using any gain elements. However …

We investigate the two-channel nonreciprocal scattering of a coherent atomic ensemble
under the linear spatial Kramers-Kronig modulation, which has potential applications in …

Microwave imaging based on the inverse scattering problem has attracted many interests in
microwave community. To obtain a satisfactory imaging quality, in most cases, a scattering …

Non-reciprocal reflections of optical signals are unusual yet fascinating to achieve the
imminent applications of non-reciprocal photonic devices and circuits. The complete non …

We propose a feasible invisibility approach to suppress the scattering of waves from or to
given directions and for particular frequencies, ie, invisibility on demand. We derive a …