Q-modulation semiconductor laser with electric absorption grating structure

Abstract

This invention discloses a Q-modulated semiconductor laser with an electric absorption structure including a distributed feed-back grating of lambda / 4 phase shift, two separated upper electrodes depositing on the top of the grating, an electrode depositing on the base of the laser as the public base, in which, the first upper electrode covers part of the grating including a phase shift region providing gain to the laser by injecting constant current, a second upper electrode covers the rest part of the grating away from the phase shift region as the Q-modulator of the laser and electric signals can be added to the second upper electrode to change the absorption coefficient of the waveguide of the modulator region and alter the Q value of the laser so as to alter the laser threshold value and output power.

Description

technical field [0001] The present invention relates to semiconductor lasers and modulators, and more particularly to a quarter-wavelength phase-shifted distributed feedback laser or distributed Bragg reflection monolithically integrated with a Q-modulator that utilizes current injection or electroabsorption effects to vary the quality factor of the laser laser. Background technique [0002] High-speed semiconductor lasers and modulators are key components of today's fiber optic communication systems. The rapid increase in Internet traffic requires these optics to handle ever greater bit rates. It is the simplest method to directly modulate the optical signal intensity by changing the bias current of the laser, and it does not require an external modulator. However, a directly modulated laser has fundamental speed limitations and also exhibits transient oscillations with a frequency equal to its relaxation oscillation frequency. Wavelength chirp is another problem with di...

AI Technical Summary

Problems solved by technology

[0006] The purpose of the present invention is to address the deficiencies in the prior art, to propose a monolithic integration of a Q-modulated semiconductor laser with an electroabsorption grating structure and a high-speed, low-chirp modulator, to solve the high cost of traditional semiconductor lasers and modulators, Difficult to integrate, wavelength chirp, complex production and other issues

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