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https://doi.org/10.3938/NPSM.69.679
Investigation of Broadband High-Brightness Quantum-Dot Structures by using Numerical Simulations
New Phys.: Sae Mulli 2019; 69: 679~684
Published online July 31, 2019;  https://doi.org/10.3938/NPSM.69.679
© 2019 New Physics: Sae Mulli.

Yudong JANG, Donghan LEE*

Department of Physics, Chungnam National University, Daejeon 34134, Korea
Correspondence to: dleee@cnu.ac.kr
Received April 16, 2019; Revised May 22, 2019; Accepted July 1, 2019.
cc This is an open-access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Abstract
A semiconductor single quantum dot is an ideal system for studying the physics of zero-dimensional quantum structures. However, emission from a single quantum dot is extremely weak because it emits single photons, so maximizing photon collection from the quantum dot is crucial. In this work, we investigated, by using numerical simulations, an efficient single quantum dot structure that had a high photon collection efficiency and a broad bandwidth. The Purcell enhancement, photon-extraction efficiency, far-field pattern, and photon-collection efficiency were calculated and compared among candidates. A broadband structure with a bottom distributed Bragg reflector (DBR) provided a bandwidth of 27.5~nm with a lens having a NA of 0.5. The expected photon-collection efficiency was 8.7\% for a NA of 0.5, which was greatly improved from 0.5\% in a bulk structure without a DBR.
PACS numbers: 73.21.La, 78.20.Bh, 78.30.Fs
Keywords: Single quantum dot, Planar micro-cavity, Collection efficiency


July 2019, 69 (7)
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