Optical phonons as a probe to determine both composition and strain in InxAl(1-x)As quantum dots embedded in an AlAs matrix

V. A. Volodin (1, 2) , M. P. Sinyukov (1) , V. A. Sachkov (3) , Mathieu Stoffel (4) , Hervé Rinnert (4) , Michel Vergnat (4)

1 A.V. Rzhanov Institute of Semiconductor Physics
2 NSU - Novosibirsk State University
3 SB RAS - Siberian Branch of the Russian Academy of Sciences
4 IJL - Institut Jean Lamour

InxAl(1-x)As quantum dots (QDs) embedded in an AlAs matrix were studied using Raman scattering and photoluminescence spectroscopy techniques. The longitudinal optical (LO) and transverse optical (TO) In-As bond vibrations frequencies are found to depend on both composition and strain. Using different scattering geometries (allowed for LO or for TO modes) we were able to obtain the experimental values of these frequencies. By comparing these values with the calculated frequencies, one can determine both the mean composition (stoichiometry parameter x) and the biaxial strain in InxAl(1-x)As QDs embedded in an AlAs matrix. Our approach is simple, non-destructive and fast.

Domaines: Science des matériaux [cond-mat.mtrl-sci]

V. A. Volodin, M. P. Sinyukov, V. A. Sachkov, Mathieu Stoffel, Hervé Rinnert, et al.. Optical phonons as a probe to determine both composition and strain in InxAl(1-x)As quantum dots embedded in an AlAs matrix. EPL - Europhysics Letters, 2014, 105 (1), ⟨10.1209/0295-5075/105/16003⟩. ⟨hal-01284794⟩