Room-temperature optical absorption in the InAs/GaAs quantum-dot superlattice under an electric field

Journal Article · Mon Aug 15 04:00:00 EDT 2011 · Semiconductors

DOI:https://doi.org/10.1134/S1063782611080203· OSTI ID:22004753

Gadzhiev, I M; Bakshaev, I O; Nevedomskii, V N; Buyalo, M S; Zadiranov, Yu M; Portnoi, E L ^[1]

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1. Russian Academy of Sciences, Ioffe Physical Technical Institute (Russian Federation)

Electroluminescence and absorption spectra of a ten-layer InAs/GaAs quantum dot (QD) superlattice built in a two-section laser with sections of equal length is experimentally studied at room temperature. The thickness of the GaAs spacer layer between InAs QD layers, determined by transmission electron microscopy, is {approx}6 nm. In contrast to tunnel-coupled QDs, QD superlattices amplify the optical polarization intensity and waveguide absorption of the TM mode in comparison with the TE mode. It is found that variations in the multimodal periodic spectrum of differential absorption of the QD superlattice structure are strongly linearly dependent on the applied electric field. Differential absorption spectra exhibit the Wannier-Stark effect in the InAs/GaAs QD superlattice, in which, in the presence of an external electric field, coupling of wave functions of miniband electron states is suppressed and a series of discrete levels called the Wannier-Stark ladder states are formed.

• OSTI ID: 22004753
• Journal Information: Semiconductors, Journal Name: Semiconductors Journal Issue: 8 Vol. 45; ISSN SMICES; ISSN 1063-7826
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ABSORPTION
ABSORPTION SPECTRA
COMPARATIVE EVALUATIONS
COUPLING
ELECTRIC FIELDS
ELECTROLUMINESCENCE
ELECTRONS
GALLIUM ARSENIDES
INDIUM ARSENIDES
LASERS
LAYERS
PERIODICITY
POLARIZATION
QUANTUM DOTS
STARK EFFECT
SUPERLATTICES
THICKNESS
TRANSMISSION ELECTRON MICROSCOPY