4 results about "Band-gap engineering" patented technology

The invention provides a method for regulating and controlling the nonlinear absorption type of a DAST-based composite film and a preparation process of the DAST-based composite film, and relates to the technical field of nonlinear optical materials. The method comprises the following steps: compounding a guest photoelectric sensitive material DAST and a subject flexible material PMMA by adopting a blade coating technology to obtain a binary DAST / PMMA subject-guest composite film; during the process, the mass fraction of the object photoelectric sensitive material in the composite film is adjusted, so that mutual conversion between a nonlinear anti-saturated absorption behavior and a saturated absorption behavior of the composite film in a femtosecond trepanning Z scanning laser system is successfully realized. Compared with existing nonlinear absorption type regulation and control technologies such as band gap engineering of two-dimensional inorganic materials, micro-nano structure construction of organic materials, functional group modification and the like, the regulation and control method is simpler, lower in cost and more beneficial to industrial processing, and has good practical application potential in the fields of laser protection, laser mode locking, optical switches and the like.

This invention belongs to the field of semiconductor optoelectronic devices, and relates to a silicon-germanium-based NPN / PNP vertical phototransistor array structure and its manufacturing method. The structure includes a substrate layer and phototransistor units. The substrate layer is an N+ type silicon substrate, serving as the supporting substrate for the common collector region and the common conductive path. The phototransistor units include multiple NPN and PNP type phototransistor units. Both the NPN and PNP type phototransistor units include an emitter region and a silicon-based phototransistor array. 1‑x Ge x Base region and collector region, Si 1‑x Ge x The thickness of the base region is 50~300nm, 0

A semiconductor device is introduced which is capable of concentrating electrons and holes into a central volume for enhanced radiative recombination and reduced non-radiative recombination, as well as enhanced optical absorption at longer wavelengths. Carrier confinement is achieved by modifying the material properties of the junction by various means, including but not limited to, strain applied to the interior or exterior region, ion implantation for band-gap engineering or defect introduction, or thermal diffusion.

This invention belongs to the field of inorganic luminescent materials technology, and discloses a germanate-based long afterglow luminescent material, its preparation method, and its uses. This luminescent material uses MReGeO4 (M = Li or Na, Re = Y, Lu or Gd) as a matrix, and introduces Bi dopant ions. 3+ and Ln 3+ Obtained; and the chemical formula of the luminescent material is M 1‑x Re 1‑y GeO4:xBi 3+ ,yLn 3+ Where x is the dopant ion Bi 3+ The proportion of alkali metal ions Li in the matrix + Or Na + The molar doping concentration is given by , and 0 < x ≤ 0.010; y is the molar doping concentration of Ln. 3+ The proportion of ions (Ln = one of Eu, Tb, Pr or Yb) in the Re content of the matrix 3+ The molar doping concentration is such that 0 ≤ y ≤ 0.001. Based on trap engineering and bandgap engineering, this invention achieves the modulation of multimode fluorescence properties such as photoluminescence, afterglow, and photo / thermal excited fluorescence. In particular, it realizes dynamic information storage and encryption of multicolor multimode fluorescent printing, providing a material basis and physical prototype for next-generation fluorescent printing information storage and anti-counterfeiting technology.