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Title: A study of polaritonic transparency in couplers made from excitonic materials

We have studied light matter interaction in quantum dot and exciton-polaritonic coupler hybrid systems. The coupler is made by embedding two slabs of an excitonic material (CdS) into a host excitonic material (ZnO). An ensemble of non-interacting quantum dots is doped in the coupler. The bound exciton polariton states are calculated in the coupler using the transfer matrix method in the presence of the coupling between the external light (photons) and excitons. These bound exciton-polaritons interact with the excitons present in the quantum dots and the coupler is acting as a reservoir. The Schrödinger equation method has been used to calculate the absorption coefficient in quantum dots. It is found that when the distance between two slabs (CdS) is greater than decay length of evanescent waves the absorption spectrum has two peaks and one minimum. The minimum corresponds to a transparent state in the system. However, when the distance between the slabs is smaller than the decay length of evanescent waves, the absorption spectra has three peaks and two transparent states. In other words, one transparent state can be switched to two transparent states when the distance between the two layers is modified. This could be achieved by applying stressmore » and strain fields. It is also found that transparent states can be switched on and off by applying an external control laser field.« less
Authors:
;  [1]
  1. Department of Physics and Astronomy, Western University, London, Ontario N6A 3K7 (Canada)
Publication Date:
OSTI Identifier:
22399242
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 117; Journal Issue: 10; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ABSORPTION SPECTRA; CADMIUM SULFIDES; COUPLING; DOPED MATERIALS; EXCITONS; LASER RADIATION; LAYERS; OPACITY; PHOTONS; POLARONS; QUANTUM DOTS; SCHROEDINGER EQUATION; STRAINS; STRESSES; TRANSFER MATRIX METHOD; VISIBLE RADIATION; ZINC OXIDES