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Author: Lichtner, Mark × Author: Radziunas, Mindaugas × End date: 2019 × Start date: 2019 × DDC: 510 × Type: Report ×

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Now showing 1 - 3 of 3
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    Stripe-array diode-laser in an off-axis external cavity : theory and experiment
    (Berlin : Weierstraß-Institut für Angewandte Analysis und Stochastik, 2009) Jechow, Andreas; Lichtner, Mark; Menzel, Ralf; Radziunas, Mindaugas; Skoczowsky, Danilo; Vladimirov, Andrei
    Stripe-array diode lasers naturally operate in an anti-phase supermode. This produces a sharp double lobe far field at angles α depending on the period of the array. In this paper a 40 emitter gain guided stripe-array laterally coupled by off-axis filtered feedback is investigated experimentally and numerically. We predict theoretically and confirm experimentally that at doubled feedback angle 2α a stable higher order supermode exists with twice the number of emitters per array period. The theoretical model is based on time domain traveling wave equations for optical fields coupled to the carrier density equation taking into account diffusion of carriers. Feedback from the external reflector is modeled using Fresnel integration.
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    Mode transitions in distributed-feedback tapered master-oscillator power-amplifier
    (Berlin : Weierstraß-Institut für Angewandte Analysis und Stochastik, 2008) Radziunas, Mindaugas; Tronciu, Vasile Z.; Bandelow, Uwe; Lichtner, Mark; Spreemann, Martin; Wenzel, Hans
    Theoretical and experimental investigations have been carried out to study the spectral and spatial behavior of monolithically integrated distributed-feedback tapered master-oscillators power-amplifiers emitting around 973 nm. Introduction of self and cross heating effects and the analysis of longitudinal optical modes allows us to explain experimental results. The results show a good qualitative agreement between measured and calculated characteristics.
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    Improving the stability of distributed-feedback tapered master-oscillator power-amplifiers
    (Berlin : Weierstraß-Institut für Angewandte Analysis und Stochastik, 2009) Tronciu, Vasile Z.; Lichtner, Mark; Radziunas, Mindaugas; Bandelow, U.; Wenzel, H.
    We report theoretical results on the wavelength stabilization in distributed-feedback master-oscillator power-amplifiers which are compact semiconductor laser devices capable of emitting a high brilliance beam at an optical power of several Watts. Based on a traveling wave equation model we calculate emitted optical power and spectral maps in dependence on the pump of the power amplifier. We show that a proper choice of the Bragg grating type and coupling coefficient allows to optimize the laser operation, such that for a wide range of injection currents the laser emits a high intensity continuous wave beam.