Role of interface potential barrier, Auger recombination and temporal coherence in In0.5Ga0.5As/GaAs quantum dot-based p-i-n light emitting diodes

Autor(es)

Singh, Mohit Kumar ^{[1, 2]} ; Bhunia, Amit ^{[1, 2]} ; Al Huwayz, Maryam ^{[3, 4]} ; Gobato, Y. Galvao ^{[5, 6]} ; Henini, Mohamed ^{[3, 7]} ; Datta, Shouvik ^{[1, 2]}

Afiliação do(s) autor(es)

^[1] Indian Inst Sci Educ & Res, Dept Phys, Pune 411008, Maharashtra - India

^[2] Indian Inst Sci Educ & Res, Ctr Energy Sci, Pune 411008, Maharashtra - India

^[3] Univ Nottingham, Sch Phys & Astron, Nottingham NG7 2RD - England

^[4] Princess Nourah Bint Abdulrahman Univ PNU, Coll Sci, Dept Phys, Riyadh 11671 - Saudi Arabia

^[5] Univ Fed Sao Carlos, Dept Fis, BR-13560905 Sao Carlos, SP - Brazil

^[6] Radboud Univ Nijmegen, High Field Magnet Lab HFML EMFL, NL-6525 ED Nijmegen - Netherlands

^[7] Univ South Africa UNISA, Coll Grad Studies, UNESCO UNISA Africa Chair Nanosci & Nanotechnol L, POB 392, Pretoria - South Africa

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF PHYSICS D-APPLIED PHYSICS; v. 52, n. 9 FEB 27 2019.
• Citações Web of Science: 0

Resumo

In this work, we investigate the mechanisms that control the electroluminescence from p-i-n heterostructures containing self-assembled In0.5Ga0.5As quantum dots embedded inside a GaAs/Al0.3Ga0.7As quantum well as a function of temperature and applied bias. Our results reveal that the carrier dynamics at the interface between the quantum dot and the quantum well play a crucial role in the electroluminescence emission. At low temperatures, two distinct emission bands are observed. Initially at low bias current, we observe broad emissions from the quantum wells and wetting layers. Another dominant and sharp emission at lower energy arises from the quantum dots, but only at higher bias currents. We discuss how a potential barrier between the quantum dots and quantum well can control the density of injected carriers undergoing optical recombination. We have also investigated the role of carrier capture and escape, quantum-confined stark effect and band-filling effects in the electroluminescence emission. In addition, we demonstrate how measurements of temporal coherence of individual spectral peaks, can detect the presence of Auger recombination in quantum dots under high injection currents. Interestingly, a significant increase in the temporal coherence of quantum dot emissions is observed, which could be due to a decrease in Auger recombination with increasing temperature. (AU)

• Processo FAPESP: 18/01808-5 - Propriedades ópticas e de transporte em altos campos magnéticos de heteroestruturas e dispositivos semicondutores baseados em materiais bidimensionais (2d)
• Beneficiário: Yara Galvão Gobato
• Modalidade de apoio: Bolsas no Exterior - Pesquisa
• Processo FAPESP: 16/10668-7 - Propriedades óticas, magneto-óticas, de transporte e magneto-transporte de materiais semicondutores bidimensionais baseados em materiais de transição dicalcogenados
• Beneficiário: Yara Galvão Gobato
• Modalidade de apoio: Auxílio à Pesquisa - Regular