Regularization of vertical-cavity surface-emitting laser emission by periodic non-Hermitian potentials

We propose a novel physical mechanism based on periodicnon-Hermitian potentials to efficiently control the complexspatial dynamics of broad-area lasers, particularly in vertical-cavity surface-emitting lasers (VCSELs), achieving a stableemission of maximum brightness. A radially dephased peri-odic r...

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Bibliographic Details
Authors: Ahmed Waseem, Waqas Waseem, Herrero Simon, Ramon|||0000-0001-5572-1540, Botey Cumella, Muriel|||0000-0001-8984-4899, Wu, Ying, Staliunas, Kestutis|||0000-0002-0539-9538
Format: article
Publication Date:2019
Country:España
Institution:Universitat Politècnica de Catalunya (UPC)
Repository:UPCommons. Portal del coneixement obert de la UPC
Language:English
OAI Identifier:oai:upcommons.upc.edu:2117/171375
Online Access:https://hdl.handle.net/2117/171375
https://dx.doi.org/10.1364/OL.44.003948
Access Level:Open access
Keyword:Semiconductor lasers
Làsers de semiconductors
Àrees temàtiques de la UPC::Física
Description
Summary:We propose a novel physical mechanism based on periodicnon-Hermitian potentials to efficiently control the complexspatial dynamics of broad-area lasers, particularly in vertical-cavity surface-emitting lasers (VCSELs), achieving a stableemission of maximum brightness. A radially dephased peri-odic refractive index and gain-loss modulations accumulatethe generated light from the entire active layer and concen-trate it around the structure axis to emit narrow, brightbeams. The effect is due to asymmetric inward radial cou-pling between transverse wave vectors for particular phasedifferences of the refractive index and gain-loss modulations.Light is confined into a central beam with large intensity,opening the path to design compact, bright, and efficientbroad-area light sources. We perform a comprehensive analy-sis to explore the maximum central intensity enhancement andconcentration regimes. This Letter reveals that the optimumschemes are those holding unidirectional inward coupling,but not fulfilling a perfect local PT-symmetry.