Configuration Disquisitions Of High Power Semiconductor Lasers

High power semiconductor lasers are playing a very important role in such fields as military affairs, industry and medical attendance, so a mass of work have been already launched into configuration design and performance optimization of high power semiconductor lasers in order to get higher light beam quality, higher efficiency, lower cost, higher reliability and portability. The work focuses on 920 nm optically pumped semiconductor vertical external-cavity surface emitting laser (OPS-VECSEL), 808 nm edge-emitting diode lasers, 980 nm vertical cavity surface emitting laser (VCSEL) and 970nm vertical cavity semiconductor optical amplifiers (VCSOA). The main work is as follows:1) Introduce the theoretical foundation of LASTIP and PICS3D, including detailed numerical modals and calculation trails and convergence issues.Improved simulation efficiency.2) The performances of 920 nm OPS-VECSEL were analyzed by using PICS3D, dealing with structure parameters. For the first time, interiorly, schemed out 3 QWs structure of 920 nm OPS-VECSEL, the main mode oscillation had been increased from 18.57dB with 1QW to 62.24dB with 3QWs, and inserted a non-absorbing layer to bate the carrier hot overflowed, in order to reduce inner loss and increase conversion efficiency. It means a lot for structure improvement and performance enhancement. 3) Considering temperature sensitivity of laser diodes (LDs) emitting at 808 nm, characteristic temperatures with different structures were calculated by using LASTIP, also test these results experimentally. When the thickness of single QW was fixed, thicker was the waveguide layer, longer was the distance light spread, light gain and inner loss were increased in different level, threshold currents and characteristic temperatures changed nonlinearly. The nonlinear relationship between waveguide layer thickness and characteristic temperature is very important for device improvement, especially for the structure design of the high characteristic temperature devices.4) Characteristic temperature of 980nm VCSEL was simulated employing PICS3D. Analysied the characteristics change when temperature changed. When the threshold current was the least, the output power was the highest, the conversion efficiency was the highest, the wavelength drift was the least, FWHM of spectrum was the least, and this temperature was the characteristic temperature. The experimental results authenticated the theoretical calculation results.Offering theoretical thereunder for getting high power output by controlling experimentation temperature.5) Based on the structure of 970nm VCSOA, the amplifier gain and bandwidth characteristics are experimentally investigated and analyzed in the reflection mode. The maximum gain amplification of 24.8 dB and optical bandwidth of 0.14 nm (25GHz) had been reached when the injection current was 57% of threshold current and signal input power was 0.7 W. This kind of broad-area VCSOA was improved not only optical gain but also saturated input power. Correlative experiment study hasn't been reported interiorly.We optimize the structure design of the wide area VCSOA of 970nm. The simulation results show that the improvement of the gain and bandwidth of the semiconductor laser can be obtained by appropriately reducing the DBR reflectivity of the emitting laser on the vertical cavity surface.