V type coupling cavity wavelength switchable semiconductor laser

Abstract

The invention discloses a V-type coupling cavity wavelength switchable semiconductor laser, comprising two optical resonant cavities, each comprising a segment of light waveguide and partial reflecting elements at the two ends; the two segments of light waveguides are arranged on a chip to form a V shape, there is no coupling at the opening end but there is a certain cross coupling at the closed end to make the laser have optimum single-mode selectivity; the first optical resonant cavity has a fixed optical length to make its resonant frequency be on a series of independent equidistant channels; the second optical resonant cavity has a certain length difference from the first one, and by changing effective refractivity of partial waveguides in the second optical resonant cavity, it can make the laser wavelengths mutually switched on a series of channels determined by the first optical resonant cavity. And the laser can further comprise one or two branch couplers or directional couplers added outside the cavity to improve coupling efficiency of external devices, and providing added modulating or space switching functions.

Description

technical field [0001] The invention relates to a semiconductor laser, in particular to a single-chip integrated wavelength-switchable single-mode semiconductor laser. Background technique [0002] Broadband tunable lasers are widely used in metropolitan area network and long-distance telecommunication. In addition to being used as a replacement light source, which can reduce inventory numbers and costs, it can also provide the possibility to design more efficient and flexible network structures. For example, the combination of tunable lasers and wavelength routers can realize spatial optical switches and reconfigurable optical add-drop multiplexing functions. [0003] Compared with external cavity tunable lasers composed of separate components, monolithic integrated semiconductor tunable lasers have many advantages, such as compact structure, low cost, and higher reliability because there are no moving parts. Traditional monolithic integrated tunable semiconductor lasers ...

AI Technical Summary

Problems solved by technology

This Y-shaped coupled cavity structure has the advantages of easy monolithic integration, no need for deep vertical etching of rectangular grooves, and low manufacturing difficulty. However, its single-mode selectivity is very poor, and the threshold gain coefficients of the main mode and the first-order side mode are poor. Only 1cm for a 450 micron long laser -1 About 10cm compared to the typical value of the general distributed feedback (DFB) laser -1 above

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