An efficient phase-matched second harmonic generation (SHG) process induced in a silicon-organic hybrid plasmonic waveguide
with a thin nonlinear polymer layer deposited on top of a silicon slab and covered by a metal cap is theoretically
proposed. Owing to the hybridization property of the waveguide modes, the SHG from mid-infrared (~ 3.1 μm) to near-infrared
wavelength (~ 1.55 μm) is achieved with small fabrication-error sensitivity and large bandwidth. The SHG efficiency
is predicted up to 8.8% for a low pumping power of 100 mW.
We come up with a model of subwavelength-diameter fiber taper-based Bragg gratings (SWDFT-BGs) and numerically
investigated the chirp characteristics of Bragg gratings written in local single-mode fiber tapers based on coupled-mode
theory and transfer matrix method. The effective modal refractive index varies along adiabatic subwavelength-diameter
fiber tapers (SWDFTs), which results in an effective chirp in grating period. Additionally, SWDFT-BGs with full width
at half maximum (FWHM) up to 4.9 nm and time-delay slope over 25 ps/nm were achieved in simulations. This offers
an idea for fabricating single-mode chirped fiber Bragg gratings using uniform phase-mask and paves ways for
waveguide dispersion engineering and wide-bandwidth optical filters.
Allergic rhinitis is a common disease. Although it is already treated well clinically by widely using a new technology laser that is very popular with patients, but it is still not found home and aboard the detail research report about the pathological changes of nasoturbinal tissues before and after laser treatment. Recently, in order to further study the histopathological changes of the oedematous nasoturbinal mucosa irradiated by Nd:YAG laser. We have made pathological observation of the biopsy.