Engineering Photocarrier Redistributions in Graphene/III-V Quantum Dot Mixed-Dimensional Heterostructures for Radiative Recombination Enhancements

Rafael Jumar Chu; Quang Nhat Dang Lung; Tsimafei Laryn; Won Jun Choi; Daehwan Jung

doi:10.1002/smll.202406197

Engineering Photocarrier Redistributions in Graphene/III-V Quantum Dot Mixed-Dimensional Heterostructures for Radiative Recombination Enhancements

Small. 2024 Nov 15:e2406197. doi: 10.1002/smll.202406197. Online ahead of print.

Authors

Rafael Jumar Chu^{1

2}, Quang Nhat Dang Lung¹, Tsimafei Laryn^{1

2}, Won Jun Choi¹, Daehwan Jung^{1

2}

Affiliations

¹ Center for Quantum Technology, Korea Institute of Science and Technology, Seoul, 02792, South Korea.
² Division of Nano and Information Technology, KIST School at Korea National University of Science and Technology, Seoul, 02792, South Korea.

PMID: 39544155
DOI: 10.1002/smll.202406197

Abstract

Integration of graphene and quantum dots (QD) is a promising route to improved material and device functionalities. Underlying the improved properties are alterations in carrier dynamics within the graphene/QD heterostructure. In this study, it is shown that graphene functions as a carrier redistribution and supply channel when integrated with InAs QDs. Photoluminescence (PL) spectroscopy provides evidence that graphene modifies the redistribution, escape, and recombination dynamics of carriers in the InAs QD ensemble, which ultimately leads to enhanced radiative recombinations at all temperatures and excitation densities probed. It is also shown that the PL enhancement from the graphene/InAs QD heterostructure is greatest with a thin GaAs cap and at higher temperatures where devices operate. This study advances the understanding of graphene/QD heterostructures and can aid the design of mixed-dimensional optoelectronic devices.

Keywords: InAs; carrier dynamics; graphene; mixed‐dimensional; photoluminescence; quantum dot.

Abstract

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