Silver selenide/selenium silver sulfide core-shell quantum dots, electrooptical modulator and preparation method

Abstract

The invention provides silver selenide / selenium silver sulfide core-shell quantum dots, an electrooptical modulator and a preparation method. According to the preparation method, octadecene-selenium is used as a selenium precursor, silver selenide quantum dots are prepared; the surfaces of the silver selenide quantum dots are coated with selenium silver sulfide alloy shells to passivate the surfaces of the silver selenide quantum dots, reduce the surface defects of the silver selenide quantum dots, construct a gentle interface barrier, inhibit auger recombination of the silver selenide quantumdots, and eliminate a local electric field in a random direction; the toxicity of the silver selenide / selenium silver sulfide core-shell quantum dots can be ignored, the silver selenide / selenium silver sulfide core-shell quantum dots are safe and reliable; perhydropolysilazane is adopted to be converted into a silicon dioxide packaging layer of the silver selenide / selenium silver sulfide core-shell quantum dots in the atmosphere and at the room temperature, and the electrooptical modulator which is continuously adjustable in working wavelength along with the size of the quantum dots in a near-infrared second window, large in modulation depth, stable in performance, long in service life, simple in structure and environmentally friendly can be prepared.

Description

technical field [0001] The invention belongs to the field of optoelectronic devices, and relates to a silver selenide / silver selenide sulfide core-shell quantum dot, an electro-optic modulator and a preparation method. Background technique [0002] The electro-optic modulator is a modulator made using the electro-optic effect. When a voltage is applied to the electro-optic crystal, the refractive index or band gap of the electro-optic crystal will change, resulting in a change in the characteristics of the light wave passing through the crystal. Modulation of the phase, amplitude, intensity, and polarization state of a signal, which is a key component in optical communication systems. [0003] Under the action of an external electric field, the quantum confinement structure will form a built-in electric field, which will lead to the tilt of the energy band of the semiconductor, the spatial separation of electron-hole pairs, and the reduction of wave function overlap, resulti...

AI Technical Summary

Problems solved by technology

However, the Auger recombination efficiency and specific surface area of ​​quantum dots are much higher than that of quantum wells, and the Auger recombination and surface defects of quantum dots will generate charged carriers on or around the surface of quantum dots, which will generate Randomly oriented local electric fields that impair the modulation depth of electro-optic modulators

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