A Single Longitudinal Mode Semiconductor Laser Based on Bandpass Filtering Structure

Abstract

The invention provides a single longitudinal mode semiconductor laser unit based on a band-pass filtering structure. The horizontal structure of the single longitudinal mode semiconductor laser unit is a ridge waveguide structure shown by an x-y section and is composed of an N-type electrode (1), a substrate (2), lower cladding (3), a lower respectively-limiting layer (4), a strain multi-quantum-well active layer (5), an upper respectively-limiting layer (6), upper cladding (7), an upper cladding ridge strip part (8) and a P-type electrode (9), wherein the N-type electrode (1), the substrate (2), the lower cladding (3), the lower respectively-limiting layer (4), the strain multi-quantum-well active layer (5), the upper respectively-limiting layer (6), the upper cladding (7), the upper cladding ridge strip part (8) and the P-type electrode (9) are sequentially ranked from bottom to top. The longitudinal structure of the single longitudinal mode semiconductor laser unit is a structure shown in the z direction and is composed of an ordinary FP cavity (10) and a band-pass filtering unit (11) located in the cavity. The band-pass filtering unit is provided with a taper chute. The single longitudinal mode semiconductor laser unit has the advantages of being simple in structure and manufacturing process, low in manufacturing cost and the like, and the requirements of ONU application in the G / 10GPON-FTTH network for high yield and low cost of the single longitudinal mode laser unit can be met.

Description

technical field [0001] The invention relates to a laser, in particular to a single longitudinal mode semiconductor laser based on a band-pass filter structure. Background technique [0002] All costs of the optical network unit (ONU) in the fiber-to-the-home (FTTH) network need to be borne by a single user. Therefore, the use of low-cost optoelectronic devices in the ONU is crucial to the popularization and development of this technology. See literature [1] (W.P.Huang, X.Li, et al., Invited tutorial IEEE / OSA J.of Lightwave Technol., 25(1), 11-27, 2007.), each involved in the ONU In the cost of optoelectronic devices, the light source (laser) accounts for the largest share (the cost of the laser is about 70% of the entire ONU cost). Therefore, the development of a low-cost semiconductor laser that can meet the performance requirements of the ONU for the light source in the FTTH network is one of the key issues related to whether the FTTH network can be popularized rapidly. ...

AI Technical Summary

Problems solved by technology

Although the DFB laser represented by this structure is currently the most mature dynamic single longitudinal mode laser product, its grating production is relatively complicated, and the device still has the following disadvantages in terms of performance:

[0006] (1) The light emitted by the rear end face (accounting for 50% of the total optical power) is wasted because it cannot be utilized;

[0007] (2) Extremely sensitive to external light feedback

However, the disadvantages of the DBR structure are: (1) the monolithic integrated butt growth technology of the passive grating waveguide and the active region waveguide is required; (2) the passive grating region must have a certain length to achieve the required side mode suppression ratio

[0009] The light source of ONU in the current G / 10GPON-FTTH network generally adopts DFB lasers based on refractive index coupling uniform gratings. At present, there are mainly problems of low yield and high cost.

Images