Optical characteristics of InAlAs/GaAlAs/GaAs quantum dots (Conference Presentation)

Baolai Liang; Diana L. Huffaker; Yuriy I. Mazur; Morgan Ware; Gregory J. Salamo; Linlin Su; Ying Wang; Qinglin Guo

doi:10.1117/12.2251605

28 April 2017 Optical characteristics of InAlAs/GaAlAs/GaAs quantum dots (Conference Presentation)

Baolai Liang, Diana L. Huffaker, Yuriy I. Mazur, Morgan Ware, Gregory J. Salamo, Linlin Su, Ying Wang, Qinglin Guo

Proceedings Volume 10114, Quantum Dots and Nanostructures: Growth, Characterization, and Modeling XIV; 101140N (2017) https://doi.org/10.1117/12.2251605
Event: SPIE OPTO, 2017, San Francisco, California, United States

Abstract

The type-I to type-II band alignment transition in InAlAsAs/AlGaAs/GaAs self-assembled quantum dots (QDs) is investigated when the Al-composition in QDs and barrier are changed. In particular, the In0.46Al0.54As/Ga0.46Al0.54As/GaAs QDs show unique optical properties. The PL peak energy has a blue-shift of >40 meV when the laser intensity increases by four orders of magnitude, indicating a type-II band alignment of the QDs. The formation of the type-II band alignment is explained by that the quantum-confinement effect pulls up the minimum electron energy level in the QDs and the Γ→X transition in the Ga0.46Al0.54As barrier. The time-resolved PL (TRPL) spectrum of QDs at peak wavelength exhibits a double-component decay behavior, suggesting the possibility of type-I and type-II band alignment coexistence in this QD sample. The continuum state of the QDs is also investigated. Emission associated with the continuum states of the QDs is directly observed in PL spectra. The PL excitation (PLE) and TRPL spectra reveal an efficient carrier relaxation from the AlGaAs barrier into the InAlAs QD ground state via the continuum states. The carrier recombination in the continuum states can compete with that in the QDs due to the long recombination lifetime in the type-II QDs. This feature of continuum state emission can not be observed for normal InGaAs/GaAs QDs with the type-I band structure.

Conference Presentation

Citation Download Citation

Baolai Liang, Diana L. Huffaker, Yuriy I. Mazur, Morgan Ware, Gregory J. Salamo, Linlin Su, Ying Wang, and Qinglin Guo "Optical characteristics of InAlAs/GaAlAs/GaAs quantum dots (Conference Presentation)", Proc. SPIE 10114, Quantum Dots and Nanostructures: Growth, Characterization, and Modeling XIV, 101140N (28 April 2017); https://doi.org/10.1117/12.2251605

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members: $17.00

Non-members: $21.00 ADD TO CART

PROCEEDINGS
PRESENTATION

WATCH
PRESENTATION SAVE TO MY LIBRARY

GET CITATION

KEYWORDS

Quantum dots

Optical properties

Current controlled current source

Nanostructures

Optical alignment

Keywords/Phrases

Search In:

Publication Years