Strain relaxation in stacked InAs/GaAs quantum dots studied by Raman scattering

Ibáñez, J.; Patanè, A.; Henini, M.; Eaves, L.; Hernández, S.; Cuscó, R.; Artús, L.; Musikhin, Yu. G.; Brounkov, P. N.

doi:10.1063/1.1618368

Cited by 37 publications

(22 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We have recently shown that the strain in stacked QD structures can be probed by Raman scattering. 14 We found that the frequency of the QD phonon peak decreases as the spacing between QD layers is reduced in samples containing ten layers of InAs/ GaAs QDs. These frequency shifts were attributed to the strain relaxation that takes place during the growth of the QD multilayer system.…”

Section: Inas/ Gaas Stacked Qdsmentioning

confidence: 89%

“…This feature is assigned to the InAs LO-like QD phonon on the basis of its frequency position and selection rules. 13,14 The QD peak in the sample containing In 0.5 Ga 0.5 As QDs is clearly shifted to lower frequencies with respect to the peak that appears in the InAs QD sample. As discussed in Sec.…”

Section: A In X Ga 1−x As Qds Versus Inas Qdsmentioning

confidence: 99%

“…5, we plot the In fraction as determined from the measured QD phonon frequencies 14 with GaAs spacer layers of thickness d ranging from 98 down to 14 Å ͑samples D1-D5 of Table I, respectively͒. By using the curve of Fig.…”

Section: Inas/ Gaas Stacked Qdsmentioning

confidence: 99%

“…A rough estimate of the confinement-induced shifts using the linear chain model 18 yields values lower than Ϸ0.5 cm −1 for the QD sizes of the samples studied in this work. 11,14 The frequency of optical phonons in strained QDs can be calculated following the approximation proposed in Ref. 11, where it is assumed that the vibrational eigenmodes involving all the atoms inside the dots experience the average QD strain field.…”

Section: Qd Optical-phonon Frequency Versus In Contentmentioning

confidence: 99%

“…Despite this drawback, it has been shown that Raman scattering may yield valuable information on QD composition and strain depending on the system under consideration. [11][12][13][14][15] For instance, the optical phonon frequencies are particularly sensitive to strain and composition in Si/ Ge QDs, 15 which allows one to evaluate possible intermixing effects that take place during the growth of the structures. In contrast, the phonon frequency shifts in other QD systems are not very sensitive to alloying effects.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Probing the intermixing in In(Ga)As∕GaAs self-assembled quantum dots by Raman scattering

Ibáñez

Cuscó

Hernández

et al. 2006

Journal of Applied Physics

Self Cite

View full text Add to dashboard Cite

We show that Raman scattering is a sensitive technique for probing the degree of Ga intermixing in In͑Ga͒As/ GaAs self-assembled quantum dots ͑QDs͒. The shifts of the QD phonon frequency that we observe are explained by the modification of the strain due to Ga incorporation into the QDs from the GaAs matrix during growth. Using an elastic continuum model, we estimate the average In content of the dots from the QD phonon frequency. The varying amount of intermixing in QDs grown with different In compositions, QD layer thicknesses, growth temperatures, and stacking spacer layer thicknesses are investigated. The Raman data indicate that Ga intermixing is larger for QD samples with low In͑Ga͒As coverage thickness and/or high growth temperature and, in multilayered systems, for samples with small GaAs spacer layers.

show abstract

Section: Inas/ Gaas Stacked Qdsmentioning

confidence: 89%

Section: A In X Ga 1−x As Qds Versus Inas Qdsmentioning

confidence: 99%

Section: Inas/ Gaas Stacked Qdsmentioning

confidence: 99%

Section: Qd Optical-phonon Frequency Versus In Contentmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Probing the intermixing in In(Ga)As∕GaAs self-assembled quantum dots by Raman scattering

Ibáñez

Cuscó

Hernández

et al. 2006

Journal of Applied Physics

Self Cite

View full text Add to dashboard Cite

show abstract

High‐field magneto‐photoluminescence of semiconductor nanostructures

Hayne

Bansal

2012

Luminescence

View full text Add to dashboard Cite

We review the photoluminescence of semiconductor nanostructures in high magnetic fields, concentrating on the effects of the applied magnetic field on orbital motion (wave function extent), which is probed in experiments on large ensembles. We present an overview of the physics of excitons in high magnetic fields in 3- and 2-D before introducing the zero-dimensional case. We then discuss the physics of quantum-dot excitons in high magnetic fields with particular attention to the approximate analytical models used to interpret experimental results. This is followed by a brief description of a typical high-field magneto-photoluminescence setup. We then present four examples of magneto-photoluminescence experiments on different materials systems chosen from our own research to illustrate how high magnetic fields can be used to reveal new insights into the physics of semiconductor nanostructures.

show abstract

The improvement of InAs/GaAs quantum dot properties capped by Graphene

Rezgui

Othmen

Cavanna³

et al. 2013

J Raman Spectroscopy

View full text Add to dashboard Cite

InAs self‐assembled quantum dots (QDs) were grown by molecular beam epitaxy on (001) GaAs substrate. Uncapped and capped QDs with GaAs and graphene layers were studied using atomic force microscopy and Raman spectroscopy. Graphene multi‐layer was grown by chemical vapor deposition and transferred on InAs/GaAs QDs. It is well known that the presence of a cap layer modifies the size, shape, and density of the QDs. According to the atomic force microscopy study, in contrast to the GaAs capped sample, which induce a dramatic decrease of the density and height of dots, graphene cap layer sample presents a slight influence on the surface morphology and the density of the islands compared with the uncapped one. The difference shown in the Raman spectra of the samples is due to change of strain and alloy disorder effects on the QDs. Residuals strain and the relaxation coefficients have been investigated. All results confirm the best crystalline quality of the graphene cap layer dots sample relative to the GaAs capped one. So graphene can be used to replace GaAs in capping InAs/GaAs dots. To our knowledge, such study has not been carried out until now. Copyright © 2013 John Wiley & Sons, Ltd.

show abstract

Strain relaxation in stacked InAs/GaAs quantum dots studied by Raman scattering

Cited by 37 publications

References 15 publications

Probing the intermixing in In(Ga)As∕GaAs self-assembled quantum dots by Raman scattering

Probing the intermixing in In(Ga)As∕GaAs self-assembled quantum dots by Raman scattering

High‐field magneto‐photoluminescence of semiconductor nanostructures

The improvement of InAs/GaAs quantum dot properties capped by Graphene

Contact Info

Product

Resources

About