Electronic band structure and optical gain of GaN{sub x}Bi{sub y}As{sub 1−x−y}/GaAs pyramidal quantum dots

Journal Article · Thu Apr 14 00:00:00 EDT 2016 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4945700· OSTI ID:22594579

Song, Zhi-Gang ^[1]; Bose, Sumanta; Fan, Wei-Jun ^[1]; Li, Shu-Shen ^[2]

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1. School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore)
2. State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, P.O. Box 912, Beijing 100083 (China)

The electronic band structure and optical gain of GaN{sub x}Bi{sub y}As{sub 1−x−y}/GaAs pyramidal quantum dots (QDs) are investigated using the 16-band k ⋅ p model with constant strain. The optical gain is calculated taking both homogeneous and inhomogeneous broadenings into consideration. The effective band gap falls as we increase the composition of nitrogen (N) and bismuth (Bi) and with an appropriate choice of composition we can tune the emission wavelength to span within 1.3 μm–1.55 μm, for device application in fiber technology. The extent of this red shift is more profound in QDs compared with bulk material due to quantum confinement. Other factors affecting the emission characteristics include virtual crystal, strain profile, band anticrossing (BAC), and valence band anticrossing (VBAC). The strain profile has a profound impact on the electronic structure, specially the valence band of QDs, which can be determined using the composition distribution of wave functions. All these factors eventually affect the optical gain spectrum. With an increase in QD size, we observe a red shift in the emission energy and emergence of secondary peaks owing to transitions or greater energy compared with the fundamental transition.

• OSTI ID: 22594579
• Journal Information: Journal of Applied Physics, Vol. 119, Issue 14; Other Information: (c) 2016 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
BISMUTH
COMPARATIVE EVALUATIONS
CONFINEMENT
CRYSTALS
ELECTRONIC STRUCTURE
EMISSION
FIBERS
GALLIUM ARSENIDES
GALLIUM NITRIDES
NITROGEN
QUANTUM DOTS
RED SHIFT
SPECTRA
STRAINS
VALENCE
WAVE FUNCTIONS
WAVELENGTHS