Simulation of spectral stabilization of high-power broad-area edge emitting semiconductor lasers

Abstract

The simulation of spectral stabilization of broad-area edge-emitting semiconductor diode lasers is presented in this paper. In the reported model light-, temperature- and charge carrier-distributions are solved iteratively in frequency domain for transverse slices along the semiconductor heterostructure using wide-angle finite-difference beam propagation. Depending on the operating current the laser characteristics are evaluated numerically, including near- and far-field patterns of the astigmatic laser beam, optical output power and the emission spectra, with central wavelength and spectral width. The focus of the model lies on the prediction of influences on the spectrum and power characteristics by frequency selective feedback from external optical resonators. Results for the free running and the spectrally stabilized diode are presented.

High-resolution setup for measuring wavelength sensitivity of photoyellowing of translucent materials

“…The principle of the spatial filter is similar as in the research by Minoni et al 18 Due to the stationary pinhole, the filtering is more effective at longer wavelengths, since its diameter was selected according to the diffraction limited spot size of the 933-nm beam of the IR diode laser, which has initially a distorted, elliptical beam profile caused by the spatial free carrier density distribution and the rectangular-shaped junction. 19,20 In the ultraviolet region, the filtering is not as good as in IR but sufficient since the beam profiles are good naturally. Also the beams are not attenuated much, which provides better signal-to-noise ratios.…”

Brightness and average power as driver for advancements in diode lasers and their applications

“…Goal of the numerical analysis is to support the design process of external feedback systems and semiconductor devices, and thus lead to shorter design cycles and reduced development costs. The multi-frequency 2D cross section laser model includes solvers for the transverse electrical, thermal and optical fields with attached external resonators for transverse and longitudinal mode selection [20] [21]. The goal is to calculate the dynamics of the electromagnetic field in diode laser edge emitters with coupled frequency-selective external resonators.…”

“…Calculated spectral stabilization with external reflectivity of 6%:normalized spectral power density (left) and spectral map in false colors with 90% power inclusion and central wavelength (right) [20]. Measured spectral stabilization with external reflectivity of 6%:normalized spectral power density (left) and spectral map in false colors with 90% power inclusion and central wavelength (right) [20].…”

“…Measured spectral stabilization with external reflectivity of 6%:normalized spectral power density (left) and spectral map in false colors with 90% power inclusion and central wavelength (right) [20]. …”

High-power dense wavelength division multiplexing of multimode diode laser radiation based on volume Bragg gratings

“…Calculations of the external resonators have been performed with the simulation software presented in [9]. The maximum diffraction efficiency of the VBGs at 0°incidence angle is 8%.…”