The effect of material dispersion on the optical properties of one-dimensional non-Hermitian scattering systems is investigated in detail. In particular, multilayer heterostructures with gain and loss (parity-time symmetric or not

In this work, we first discuss systematically three general approaches to construct a non-Hermitian flat band, defined by its dispersionless real part. These approaches resort to, respectively, spontaneous restoration of non-Hermi

We propose a parity-time (PT) symmetric fiber laser composed of two coupled ring cavities with gains and losses, which operates both in PT-symmetric and symmetry-broken regimes depending on the static phase shifts. We perform anal

Integrated nonlinear waveguide structures enable generation of quantum entangled photons. We describe theoretically the effects of spatially inhomogeneous loss on the creation of photon pairs through spontaneous parametric down-co

Transparent conductive oxides have emerged as a new type of plasmonic material and demonstrated unique electro-optic (E-O) modulation capabilities for next-generation photonic devices. In this paper, we report an ultra-compact, br

High-performance GaInP/AlGaInP multi-quantum well light-emitting diodes (LEDs) grown on a low threading dislocation density (TDD) germanium-on-insulator (GOI) substrate have been demonstrated. The low TDD of the GOI substrate is r

In this paper, the fabrication process and characterization of Bi2Te3 topological insulators (TIs) synthesized by the spin-coating-coreduction approach (SCCA) is reported. With this approach, high-uniformity nano-crystalline TI sa

We report on the first electrically pumped continuous-wave (CW) InAs/GaAs quantum dot (QD) laser grown on Si with a GaInP upper cladding layer. A QD laser structure with a Ga0.51In0.49P upper cladding layer and an Al0.53Ga0.47As l

A noise-sidebands-free and ultra-low relative intensity noise (RIN) 1.5 μm single-frequency fiber laser is demonstrated for the first time to our best knowledge. Utilizing a self-injection locking framework and a booster optical a

A microcavity laser based on evanescent-wave-coupled gain is formed using a silica fiber with a diameter of 125 μm in a rhodamine 6G ethanol solution. When the fiber is sticking to the cuvette wall by capillary force, using the ex

Er/Ho co-doped oxyfluoride germanosilicate glass and glass ceramics are prepared and compared. The results indicate that the glass consists of SiO4 and GeO4 structural units, while the network of the glass ceramics consists of SiO

For the first time to our knowledge, graphitic carbon nitride (g-C3N4) nanosheets are found to be an excellent saturable absorber material in the visible waveband. g-C3N4 exhibits much stronger saturable absorption in this region

We investigate frequency-comb generation in normal dispersion silicon microresonators from the near-infrared to mid-infrared wavelength range in the presence of multiphoton absorption and free-carrier effects. It is found that par

In this paper, for the first time to our knowledge in the literature, we demonstrate photoluminescence from two-dimensional (2D) vanadium diselenide (VSe2) nanosheets (NSs). The preparation of these nanostructures is carried out w

Connected-annular-rods photonic crystals (CARPCs) in both triangular and square lattices are proposed to enhance the two-dimensional complete photonic bandgap (CPBG) for chalcogenide material systems with moderate refractive index

We propose an efficient and robust method to generate tunable vector beams by employing a single phase-type spatial light modulator (SLM). With this method, a linearly polarized Gaussian beam can be converted into a vector beam wi

Silicon has been the material of choice of the photonics industry over the last decade due to its easy integration with silicon electronics, high index contrast, small footprint, and low cost, as well as its optical transparency i

X-ray absorption spectroscopy is proposed as a method for studying the heating of solid-density matter excited by secondary X-ray radiation from a relativistic laser-produced plasma. The method was developed and applied to experim

In this work, it has been demonstrated that in order to fully understand the terahertz (THz) pulse generation process during femtosecond laser filamentation, the interaction between THz wave and air plasma has to be taken into acc