Abstract
The photoluminescence and excitation of luminescence spectra of a series of samples containing two CdTe layers D1 and D2 with a nominal thickness of 1.5 and 4 monolayers in a ZnTe matrix were studied. The samples differ in the width of the ZnTe spacer separating the D1 and D2 inserts and constituting 15, 25, 35, 45 and 55 monolayers (samples nos. 1–5, respectively). ZnTe layers are grown on a GaAs substrate by the standard molecular beam epitaxy mode, while CdTe inserts are grown in atomic layer epitaxy mode. It is shown that when the barrier thickness is less than 25 monolayers electronic states in the quantum wells formed by D1 and D2 layers are tunnel-coupled, and only one band is recorded in the emission spectrum, caused by the recombination of excitons in the deep quantum well. At larger thicknesses of the spacer, two bands I1 and I2 are observed in the luminescence spectrum, which are associated with the recombination of excitons in shallow (D1) and deep (D2) wells, respectively. It was found that the intensity ratio I1/I2 significantly depends on the energy and intensity of the excitation. Possible origin of these dependences are discussed.
Similar content being viewed by others
REFERENCES
G. V. Budkin, M. V. Eremenko, and A. N. Reznitsky, J. Exp. Theor. Phys. 124, 740 (2017).
G. V. Budkin and A. N. Reznitsky, Semiconductors 52, 1795 (2018).
A. N. Reznitsky, A. A. Klochikhin, and S. A. Permogorov, Phys. Solid State 54, 123 (2012).
Funding
M.C. and A.R. acknowledge the support from Presidium RAS Program no. 5: “Photonic technologies in probing inhomogeneous media and biological objects”, G.K. acknowledges the support from National Science Centre (Poland) grants nos. 2017/25/B/ST3/02966 and 2018/30/M/ST3/00276.
Author information
Authors and Affiliations
Corresponding authors
Ethics declarations
The authors declare that they have no conflict of interest.
Rights and permissions
About this article
Cite this article
Agekyan, V., Chukeev, M., Karczewski, G. et al. Exciton Spectra and Energy Transfer in CdTe/ZnTe Double Quantum Wells Grown by Atomic-Layer Epitaxy. Semiconductors 53, 2060–2063 (2019). https://doi.org/10.1134/S1063782619120029
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1134/S1063782619120029