Semiconductor laser wavelength stabilizing system and realization method

Abstract

The invention particularly relates to a method and a system for stabilizing a semiconductor laser wavelength. The semiconductor laser wavelength stabilizing system comprises a control unit, a driving power supply, a heat sink and a temperature sensor for detecting the temperature of the heat sink, wherein the driving power supply is a pulse current source capable of adjusting forward bias current; the semiconductor laser and the temperature sensor are both arranged on the heat sink; and the control unit is internally provided with a mathematical model for expressing the relationship between the bias current and the heat sink temperature for calculating the DC bias current value which needs to be loaded according to the detected heat sink temperature value. Through indirectly measuring the temperature of the heat sink of the semiconductor laser, stable laser wavelength output is realized through adjusting the bias DC value of the driving power supply, the structure of the system is simple, no extra heating or cooling components are needed, and no extra optical components are needed.

Description

technical field [0001] The invention belongs to the field of semiconductor laser pumping, and in particular relates to a method and system for stabilizing the wavelength of a semiconductor laser. Background technique [0002] The wavelength of semiconductor lasers has significant drift due to the influence of operating temperature and current. For example, for general 808nm or 9xx semiconductor lasers, there is a drift coefficient of 0.2-0.3nm / ℃. Wavelength drift will affect the application of semiconductor lasers. For example, when a semiconductor laser is used for solid-state laser pumping, the wavelength drift will cause a mismatch with the absorption spectrum of the solid-state laser gain medium, resulting in a decrease in pumping efficiency. [0003] Currently commonly used wavelength stabilization techniques include the following three methods, but all of them have problems. Take the pump application as an example: [0004] 1) Use Volume Bragg Grating (VBG) to lock th...

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Problems solved by technology

[0004] 1) Use Volume Bragg Grating (VBG) to lock the wavelength: Although the VBG wavelength locking technology can control the temperature drift coefficient to about 0.01nm / ℃, it needs to use an optical collimator lens (such as the fast axis collimator lens FAC) when the technology is implemented. and VBG components, the overall volume is large, which limits its application in high-power side pump modules;

[0005] 2) Use DFB (Distributed Feedback) or DBR (Distributed Bragg Reflector) laser structure: the power density of DFB or DBR semiconductor laser is relatively low, and its manufacturing cost is high, making it difficult to apply to high-power pump sources;

[0006] 3) Using water cooling or TEC (Thermal-electric Cooler) to control the working temperature of the laser, etc. Maintaining the spectrally stable output of the semiconductor laser through water cooling or TEC temperature control is currently the most used method in high-power pumping, but temperature control The system generally needs to adjust the temperature of the entire pump module. Since the heat transfer path between the cold source or heat source for temperature control and the semiconductor laser is relatively long, its response time is slow; in addition, the temperature control system will increase the temperature of the entire pump module. The total volume of the Pu module

Therefore, the above scheme has not been practically promoted and applied.

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