Filters

2006 - 200922010 - 20153

More filters

20195
Reset filters

Settings

Publisher: Berlin : Weierstraß-Institut für Angewandte Analysis und Stochastik × Subject: semiconductor lasers ×

Search Results

Now showing 1 - 5 of 5
  • Thumbnail Image
    Item
    Bistability and hysteresis in an optically injected two-section semiconductor laser
    (Berlin : Weierstraß-Institut für Angewandte Analysis und Stochastik, 2014) Pimenov, Alexander; Viktorov, Evgeniy A.; Hegarty, Stephen P.; Habruseva, Tatiana; Huyet, Guillaume; Rachinskii, Dmitrii; Vladimirov, Andrei G.
    The effect of coherent single frequency injection on two-section semiconductor lasers is studied numerically using a model based on a set of delay differential equations. The existence of bistability between different CW and non-stationary regimes of operation is demonstrated in the case of sufficiently large linewidth enhancement factors.
  • Thumbnail Image
    Item
    Timing jitter of passively mode-locked semiconductor lasers subject to optical feedback : a semi-analytic approach
    (Berlin : Weierstraß-Institut für Angewandte Analysis und Stochastik, 2015) Jaurigue, Lina; Pimenov, Alexander; Rachinskii, Dmitrii; Schöll, Eckehard; Lüdge, Kathy; Vladimirov, Andrei G.
    We propose a semi-analytical method of calculating the timing fluctuations in modelocked semiconductor lasers and apply it to study the effect of delayed coherent optical feedback on pulse timing jitter in these lasers. The proposed method greatly reduces computation times and therefore allows for the investigation of the dependence of timing fluctuations over greater parameter domains. We show that resonant feedback leads to a reduction in the timing jitter and that a frequency-pulling region forms about the main resonances, within which a timing jitter reduction is observed. The width of these requency pulling regions increases linearly with short feedback delay times. We derive an analytic expression for the timing jitter, which predicts a monotonic decrease in the timing jitter for resonant feedback of increasing delay lengths, when timing jitter effects are fully separated from amplitude jitter effects. For long feedback cavities the decrease in timing jitter scales approximately as 1/tau with the increase of the feedback delay time tau.
  • Thumbnail Image
    Item
    Timing jitter in passively mode-locked semiconductor lasers
    (Berlin : Weierstraß-Institut für Angewandte Analysis und Stochastik, 2014) Pimenov, Alexander; Rachinskii, Dmitrii; Habruseva, Tatiana; Hegarty, Stephen P.; Guillaume, Huyet; Vladimirov, Andrei G.
    We study the effect of noise on the dynamics of passively mode-locked semiconductor lasers both experimentally and theoretically. A method combining analytical and numerical approaches for estimation of pulse timing jitter is proposed. We investigate how the presence of dynamical features such as wavelength bistability affects timing jitter.
  • Thumbnail Image
    Item
    Electronic states in semiconductor nanostructures and upscaling to semi-classical models
    (Berlin : Weierstraß-Institut für Angewandte Analysis und Stochastik, 2006) Koprucki, Thomas; Kaiser, Hans-Christoph; Fuhrmann, Jürgen
    In semiconductor devices one basically distinguishes three spatial scales: The atomistic scale of the bulk semiconductor materials (sub-Angstroem), the scale of the interaction zone at the interface between two semiconductor materials together with the scale of the resulting size quantization (nanometer) and the scale of the device itself (micrometer). The paper focuses on the two scale transitions inherent in the hierarchy of scales in the device. We start with the description of the band structure of the bulk material by kp Hamiltonians on the atomistic scale. We describe how the envelope function approximation allows to construct kp Schroedinger operators describing the electronic states at the nanoscale which are closely related to the kp Hamiltonians. Special emphasis is placed on the possible existence of spurious modes in the kp Schroedinger model on the nanoscale which are inherited from anomalous band bending on the atomistic scale. We review results of the mathematical analysis of these multi-band kp Schroedinger operators. Besides of the confirmation of the main facts about the band structure usually taken for granted ...
  • Thumbnail Image
    Item
    Polarization properties in the transition from below to above lasing threshold in broad-area vertical-cavity surface-emitting lasers
    (Berlin : Weierstraß-Institut für Angewandte Analysis und Stochastik, 2009) Schulz-Ruhtenberg, Malte; Babushkin, Ihar; Loiko, Natalia Aleksandrovna; Huang, K.F.; Ackemann, T.
    For highly divergent emission of broad-area vertical-cavity surface-emitting lasers (VCSELs) a rotation of the polarization direction by up to 90 degrees occurs when the pump rate approaches the lasing threshold. Well below threshold the polarization is parallel to the direction of the transverse wave vector and is determined by the transmissive properties of the Bragg reflectors that form the cavity mirrors. In contrast, near-threshold and above-threshold emission is more affected by the reflective properties of the reflectors and is predominantly perpendicular to the direction of transverse wave vectors. Two qualitatively different types of polarization transition are demonstrated: an abrupt transition, where the light polarization vanishes at the point of the transition, and a smooth one, where it is significantly nonzero during the transition.