Impact of dislocations in monolithic III-V lasers on silicon: A theoretical approach

Constanze Hantschmann, Zizhuo Liu, Mingchu C. Tang, Alwyn J. Seeds, Huiyun Liu, Ian H. White, Richard V. Penty

Research output: Chapter or section in a book/report/conference proceedingChapter in a published conference proceeding

1 Citation (SciVal)


The growth of reliable III-V quantum well (QW) lasers on silicon remains a challenge as yet unmastered due to the issue of carrier migration into dislocations. We have recently compared the functionality of quantum dots (QDs) and QWs in the presence of high dislocation densities using rate equation travelling-wave simulations, which were based on 10-μm large spatial steps, and thus only allowed the use of effective laser parameters to model the performance degradation resulting from dislocation-induced carrier loss. Here we increase the resolution to the sub-micrometer level to enable the spatially resolved simulation of individual dislocations placed along the longitudinal cavity direction in order to study the physical mechanisms behind the characteristics of monolithic 980 nm In(Ga)As/GaAs QW and 1.3 μm QD lasers on silicon. Our simulations point out the role of diffusion-assisted carrier loss, which enables carrier migration into defect states resulting in highly absorptive regions over several micrometers in QW structures, whereas QD active regions with their efficient carrier capture and hence naturally reduced diffusion length show a higher immunity to defects. An additional interesting finding not accessible in a lower-resolution approach is that areas of locally reduced gain need to be compensated for in dislocation-free regions, which may lead to increased gain compression effects in silicon-based QD lasers with limited modal gain.

Original languageEnglish
Title of host publicationPhysics and Simulation of Optoelectronic Devices XXVIII
EditorsBernd Witzigmann, Marek Osinski, Yasuhiko Arakawa
ISBN (Electronic)9781510633117
Publication statusPublished - 2 Mar 2020
EventPhysics and Simulation of Optoelectronic Devices XXVIII 2020 - San Francisco, USA United States
Duration: 3 Feb 20206 Feb 2020

Publication series

NameProceedings of SPIE - The International Society for Optical Engineering
ISSN (Print)0277-786X
ISSN (Electronic)1996-756X


ConferencePhysics and Simulation of Optoelectronic Devices XXVIII 2020
Country/TerritoryUSA United States
CitySan Francisco

Bibliographical note

Funding Information:
This project is in part funded by the UK EPSRC. C. Hantschmann wishes to thank Qualcomm Inc. for PhD funding as well as MKS Instruments for the SPIE Student Travel Grant.

Publisher Copyright:
© 2020 SPIE.

Copyright 2020 Elsevier B.V., All rights reserved.


  • Photonic integration
  • quantum dot lasers
  • quantum well lasers
  • semiconductor defects
  • semiconductor laser modelling
  • silicon photonics

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Computer Science Applications
  • Applied Mathematics
  • Electrical and Electronic Engineering


Dive into the research topics of 'Impact of dislocations in monolithic III-V lasers on silicon: A theoretical approach'. Together they form a unique fingerprint.

Cite this