Polarization Response in InAs Quantum Dots: Theoretical Correlation   between Composition and Electronic Properties
  III-V growth and surface conditions strongly influence the physical structure and resulting optical properties of self-assembled quantum dots (QDs). Beyond the design of a desired active optical wavelength, the polarization response of QDs is of particular interest for optical communications and quantum information science. Previous theoretical studies based on a pure InAs QD model failed to reproduce experimentally observed polarization properties. In this work, multi-million atom simulations are performed to understand the correlation between chemical composition and polarization properties of QDs. A systematic analysis of QD structural parameters leads us to propose a two layer composition model, mimicking In segregation and In-Ga intermixing effects. This model, consistent with mostly accepted compositional findings, allows to accurately fit the experimental PL spectra. The detailed study of QD morphology parameters presented here serves as a tool for using growth dynamics to engineer the strain field inside and around the QD structures, allowing tuning of the polarization response. 
Muhammad Usman, Vittorianna Tasco, Maria Teresa Todaro, Milena De   Giorgi, Eoin P. O'Reilly, Gerhard Klimeck, and Adriana P...
physics.comp-ph cond-mat.mes-hall cond-mat.mtrl-sci quant-ph