相关论文: Single-pass, second harmonic generation of ultrafa…

We demonstrate highly efficient generation of coherent 420nm light via up-conversion of near-infrared lasers in a hot rubidium vapor cell. By optimizing pump polarizations and frequencies we achieve a single-pass conversion efficiency of…

The past decade has seen tremendous progress in the production and utilization of vortex and vector laser pulses. Although both are considered as structured light beams, the vortex lasers have helical phase fronts and phase singularities,…

We experimentally study the behavior of orbital angular momentum (OAM) of light in a noncollinear second harmonic generation (SHG) process. The experiment is performed by using a type I BBO crystal under phase matching conditions with…

Vector vortex beams simultaneously carrying spin and orbital angular momentum of light promise additional degrees of freedom for modern optics and emerging resources for both classical and quantum information technologies. The inherently…

A vortex beam, akin to a quantized vortex in superfluids, possesses inherent orbital angular momentum (OAM), resulting in the propagation of a spiral-shaped wavefront. Here we demonstrate that a pulsed vortex beam with OAM in the terahertz…

Nonlinear optical generation has been a well-established way to realize frequency conversion in nonlinear optics, whereas previous studies were just focusing on the scalar light fields. Here we report a concise yet efficient experiment to…

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 report on the generation of optical vortices with few-cycle pulse durations, 500$\mu$J per pulse, at a repetition rate of 1 kHz. To do so, a 25 fs laser beam at 800 nm is shaped with a helical phase and coupled into a hollow core fiber…

Intense spatial or spatiotemporal vortex pulses from the extreme ultraviolet to soft X-ray spectral windows are expected to provide new degrees of freedom for a variety of key applications since they carry longitudinal or transverse orbital…

We originally demonstrate the vortex beams with patterns of closed polygons [namely polygonal vortex beams (PVBs)] generated by a quasi-frequency-degenerate (QFD) Yb:CALGO laser resonator with astigmatic transformation. The PVBs with…

Structured light beams, such as optical vortices carrying orbital angular momentum, are essential for applications ranging from low-power optical communications to high-intensity laser-matter interactions. However, scaling their power and…

High harmonic generation (HHG) is a manifestation of the strongly nonlinear response of matter to intense laser fields and has, as the basis for coherent XUV sources a variety of applications. Recently, HHG from atoms in a phase and…

High harmonic generation (HHG) in solids could enable attosecond and ultraviolet light sources with high compactness, great controllability and rich functions. However, the HHG process is accompanied by a quite large wavevector mismatch…

A ~545 mW single-frequency tunable 520 nm green laser has been demonstrated using a periodically-poled potassium titanyl phosphate (PPKTP) bulk crystal based on single-pass third-harmonic generation (THG) of a 1560 nm laser via single-pass…

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…

We demonstrate unexpectedly strong second harmonic generation (SHG) in Argon gas by use of spatiotemporally focused (SF) femtosecond laser pulses. The resulting SHG by the SF scheme at a 75 cm distance shows a significantly enhanced…

Second-harmonic generation (SHG) is a fundamental tool in modern laser technology, enabling coherent frequency conversion to remote optical bands, serving as the basis for self-referenced femtosecond lasers and quadrature-squeezed light…

We demonstrate a High-Harmonic-Generation scheme which offers control over the bandwidth of the spectral peaks. The scheme uses a vectorial two-color driver with close central frequencies, generated by spectrally splitting a…

We realize a robust and compact cylindrical vector beam generator which consists of a simple two-element interferometer composed of a beam displacer and a cube beamsplitter. The interferometer operates on the higher-order Poincare sphere…

A new method to generate and control the amplitude and phase distributions of a optical vortex beam is proposed. By introducing a holographic grating on top of the dielectric waveguide, the free space vortex beam and the in-plane guiding…