WIAS Preprint No. 2488, (2018)

Modeling of current spreading in high-power broad-area lasers and its impact on the lateral far field divergence


  • Zeghuzi, Anissa
  • Radziunas, Mindaugas
    ORCID: 0000-0003-0306-1266
  • Wenzel, Hans
    ORCID: 0000-0003-1726-0223
  • Wünsche, Hans-Jürgen
  • Bandelow, Uwe
    ORCID: 0000-0003-3677-2347
  • Knigge, Andrea

2010 Mathematics Subject Classification

  • 78A60 35Q60 78M34 78-04

2008 Physics and Astronomy Classification Scheme

  • 42.55.Px 02.30.Jr 02.60.Lj


  • High-power diode laser, current spreading, current modeling, lateral far-field




The effect of current spreading on the lateral far-field divergence of high-power broad-area lasers is investigated with a time-dependent model using different descriptions for the injection of carriers into the active region. Most simulation tools simply assume a spatially constant injection current density below the contact stripe and a vanishing current density beside. Within the drift-diffusion approach, however, the injected current density is obtained from the gradient of the quasi-Fermi potential of the holes, which solves a Laplace equation in the p-doped region if recombination is neglected. We compare an approximate solution of the Laplace equation with the exact solution and show that for the exact solution the highest far-field divergence is obtained. We conclude that an advanced modeling of the profiles of the injection current densities is necessary for a correct description of far-field blooming in broad-area lasers.

Appeared in

  • Proceedings of ``SPIE Photonics West 2018'', San Francisco, USA, 21.01.2018 - 01.02.2018, B. Witzigmann, M. Osiński, Y. Arakawa, eds., vol. 10526 of Proceedings of SPIE, SPIE Digital Library, Bellingham, 2018, pp. 10526/1--10526/10, DOI 10.1117/12.2289803 .

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