Related papers: Backward phase-matched second-harmonic generation …
The high-order harmonic generation (HHG), if phase matched, opens a unique way to produce coherent ultrafast extreme-UV (XUV) or soft x-ray light sources. Here we describe a robust and tunable method for scaling and narrowing the bandwidth…
Metasurfaces with local phase tuning by subwavelength elements promise unprecedented possibilities for ultra-thin and multifunctional optical devices, in which geometric phase design is widely used due to its resonant-free and large…
Silicon photonics lacks a second-order nonlinear optical response in general because the typical constituent materials are centro-symmetric and lack inversion symmetry, which prohibits second-order nonlinear processes such as second…
Topological photonics enables robust light manipulation with third-order optical nonlinearity, yet integrating second-order optical nonlinearity into a topological system faces fundamental challenges: frequency-dependent topological…
We have studied on optical second harmonic generations (SHGs) from atomically thin MoTe2 flakes with 2H and 1T' phases. From 2H-MoTe2 samples with odd (even) numbers of layers, strong (negligible) SHGs are observed due to the…
We present a hybrid device platform for creating an electrically reconfigurable metasurface formed by the integration of plasmonic nanostructures with phase-change material germanium antimony telluride (GST). By changing the phase of GST…
Nonlinear optical processes in whispering gallery mode (WGM) microresonators have attracted much attention. Owing to the strong confinement of light in a small volume, a WGM microresonator can dramatically boost the strength of light field,…
Two-dimensional Transition-Metal Dichalcogenides (TMDs) are of great interest for second harmonic (SH) generation due to their large second-order susceptibility, atomically thin structure, and relaxed phase-matching conditions. TMDs are…
Strong light-matter coupling within electromagnetic environments provides a promising path to modify and control chemical and physical processes. The origin of the enhancement of nonlinear optical processes such as second-harmonic and…
Achieving compact and efficient visible laser sources is crucial for a wide range of applications. However traditional semiconductor laser technology faces difficulties in producing high-brightness green light, leaving a green gap in…
We study cascaded harmonic generation of hybrid surface plasmons in integrated planar waveguides composed of a graphene layer and a doped-semiconductor slab. We derive a comprehensive model of cascaded third harmonic generation through…
High-harmonic generation (HHG) provides the only source of attosecond pulses -- currently the shortest accessible time intervals, and it is employed as the only table-top source of light in extreme UV and soft X-ray spectral regions. Chiral…
The outstanding optical properties for plasmon resonances in noble metal nanoparticles enable the observation of non-linear optical processes such as second-harmonic generation (SHG) at the nanoscale. Here, we investigate the SHG process in…
Improving the conversion efficiency is critical for advancing nonlinear photonic devices, enabling applications in ultrafast optics, quantum light sources, and high-resolution imaging. Herein, we present a bilayer waveguide integrated with…
We report the observations of unexpected layer-dependent, strong, and anisotropic second harmonic generations (SHGs) in atomically thin ReS2. Appreciable (negligible) SHGs are obtained from even (odd) numbers of ReS2 layers, which is…
Harmonic generation in underdense spatially homogeneous plasma is generally expected to be inefficient: in an unmagnetized uniform plasma the fundamental and its harmonics cannot be phase-matched, resulting in third-harmonic generation…
Since the discovery of the laser, optical parametric nonlinearities have been at the core of efficient light conversion sources. Typically, thick transparent crystals or quasi-phase matched waveguides, are utilized in conjunction with…
Generation of second-harmonic waves is one of the universal nonlinear phenomena that have found numerous technical applications in many modern technologies, in particular, in photonics. This phenomenon also has great potential in the field…
We study nonlinear effects in two-dimensional photonic metasurfaces supporting topologically-protected helical edge states at the nanoscale. We observe strong third-harmonic generation mediated by optical nonlinearities boosted by…
We demonstrate second harmonic generation (SHG) in an $x$-cut congruent lithium niobate (LN) whispering gallery mode resonator. We first show theoretically that independent control of the coupling of the pump and signal modes is optimal for…