Tera-hertz and infrared frequency band laser light source

Abstract

The invention discloses a tera-hertz and infrared frequency band laser light source, which comprises a planar metal structure layer, a semiconductor active layer and a metal bottom plate layer, wherein the metal bottom plate layer is a support layer; the semiconductor active layer and the planar metal structure layer are overlapped on the metal bottom plate layer in sequence to form a coherent surface state; and the planar metal structure layer consists of one-dimensional or two-dimensional periodically-arranged metal units or metal gratings with concentric ring structures. The coherent surface state is coupled with external plane waves through a metal gap of the planar metal structure layer and is radiated to a free space, and the ratio of the metal gap of the planar metal structure layer to a unit cycle length is in an inverse relation with a coupling coefficient, so that the electromagnetic field intensity of the semiconductor active layer is amplified, and quantum number reversion is realized to generate lasing. The laser light source disclosed by the invention has a wide frequency band, high light power and a simple structure and is convenient to manufacture.

Description

technical field [0001] The invention relates to a laser light source for terahertz and infrared frequency bands. Background technique [0002] Terahertz waves refer to electromagnetic waves with a frequency range of 0.1-10 THz. The terahertz spectrum of matter contains rich physical and chemical information, and has broad application prospects in the fields of physics, chemistry, biomedicine, space communication, and military applications. Infrared frequency band refers to electromagnetic waves with frequencies between visible light and terahertz bands. Infrared spectroscopy has a wide range of applications, provides a lot of information and is characteristic, and can be applied to the analysis of the chemical composition of substances. It is not limited by melting point, boiling point and vapor pressure, and the amount of sample used is small and recyclable, which belongs to non-destructive analysis. It has become the most commonly used and indispensable tool in modern st...

AI Technical Summary

Problems solved by technology

The quantum well sub-band transition efficiency is relatively low, and the quantum cascade laser improves the external quantum efficiency and reduces the threshold current through the periodic repetition (usually up to dozens of times) of the active region and the implanted region

Each periodic unit is composed of multiple barrier layers and potential well layers, which leads to hundreds of quantum well layers and barrier layers of quantum cascade lasers. The preparation process is quite complicated and requires high-precision molecular beam epitaxial technology, greatly increasing the cost price

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