Enhancing second harmonic generation by Q-boosting lossless cavities beyond the time bandwidth limit
Nanostructures proved to be versatile platforms to control the electromagnetic field at subwavelength scale. Indeed, high-quality-factors nanocavities have been used to boost and control nonlinear frequency generation by increasing the light–matter …
MHz repetition rate femtosecond radially polarized vortex laser direct writing Yb:CaF_2 waveguide laser operating in continuous-wave and pulsed regimes
In this paper, we report the use of femtosecond radially polarized vortex laser with MHz repetition rate for direct writing of cladding waveguides (WGs) and realization of waveguide laser oscillations in ytterbium-doped calcium fluoride crystal. The negative …
Redundancy-free integrated optical convolver for optical neural networks based on arrayed waveguide grating
Optical neural networks (ONNs) have gained significant attention due to their potential for high-speed and energy-efficient computation in artificial intelligence. The implementation of optical convolutions plays a vital role in ONNs, as they are fundamental …
Grating-lobe-free optical phased array with 2-D circular sparse array aperture and high-efficiency phase calibration
An optical phased array (OPA) with 2-D circular sparse array aperture has been proposed and demonstrated in the silicon integrated photonic platform. The sparse distribution of the antenna array can realize no grating lobes in 2-D full field of view (FOV). To …
Active Huygens’ metasurface based on in-situ grown conductive polymer
Active metasurfaces provide unique advantages for on-demand light manipulation at a subwavelength scale for emerging visual applications of displays, holographic projectors, optical sensors, light detection and ranging (LiDAR). These applications put …
Topological n-root Su–Schrieffer–Heeger model in a non-Hermitian photonic ring system
Square-root topology is one of the newest additions to the ever expanding field of topological insulators (TIs). It characterizes systems that relate to their parent TI through the squaring of their Hamiltonians. Extensions to 2^n-root topology, where n is …
Scan-less microscopy based on acousto-optic encoded illumination
Several optical microscopy methods are now available for characterizing scientific and industrial processes at sub-micron resolution. However, they are often ill-suited for imaging rapid events. Limited by the trade-off between camera frame-rate and …
Orthogonally and linearly polarized green emission from a semipolar InGaN based microcavity
Polarized light has promising applications in biological inspections, displays, and precise measurements. Direct emission of polarized light from a semiconductor device is highly desired in order to reduce the size and energy-consumption of the whole system. …
Twelve-channel LAN wavelength-division multiplexer on lithium niobate
A twelve-channel local-area-network (LAN) wavelength-division multiplexing (LWDM) filter is proposed and demonstrated with a uniform channel spacing of 4.5 nm (800 GHz) in the O-band of 1270–1330 nm by using x-cut lithium-niobate-on-insulator (LNOI) …
Prominently enhanced luminescence from a continuous monolayer of transition metal dichalcogenide on all-dielectric metasurfaces
2D materials such as transition metal dichalcogenides (TMDCs) are a new class of atomic-layer materials possessing optical and electric properties that significantly depend on the number of layers. Electronic transitions can be manipulated in artificial …