450 meV hole localization in GaSb/GaAs quantum dots

Geller, M.; Kapteyn, C.; Müller-Kirsch, L.; Heitz, R.; Bimberg, D.
April 2003
Applied Physics Letters;4/21/2003, Vol. 82 Issue 16, p2706
Academic Journal
The electronic properties of self-organized GaSb quantum dots (QDs) embedded in GaAs n[SUP+] p diodes were investigated by capacitance-voltage and deep level transient spectroscopy. The localization energy of the hole ground state is 450 meV. State filling lowers the activation energy to 150 meV for completely charged QDs containing 15 holes. The hole retention time at room temperature for a single hole per QD is extrapolated to be in the microsecond range, about five orders of magnitude longer than in In(Ga)As/GaAs QDs. Hence, we consider GaSb/GaAs to be a suitable material system for future QD memory applications which require long storage times.


Related Articles

  • Optical properties of a tip-induced quantum dot. Kemerink, M.; Sauthoff, K.; Koenraad, P.M.; Gerritsen, J.W.; van Kempen, H.; Fomin, V.M.; Wolter, J.H.; Devreese, J.T. // Applied Physics A: Materials Science & Processing;2001, Vol. 72 Issue 8, pS239 

    Abstract. We have performed optical spectroscopy measurements on a STM-tip-induced quantum dot in a GaAs layer. The dominant confinement in the (hole) quantum dot is found to be in the direction parallel to the tip axis. Electron confinement is achieved by a sub-surface AlGaAs barrier....

  • The influence of size distribution on the luminescence decay from excited states of InAs/GaAs self-assembled quantum dots. Harbord, Edmund; Spencer, Peter; Clarke, Edmund; Murray, Ray // Journal of Applied Physics;Feb2009, Vol. 105 Issue 3, pN.PAG 

    We compare the time integrated and time resolved spectra of two samples having coincident ground state emission peaks: one consisting of highly uniform quantum dots, the other grown under conditions which produce a broad distribution of quantum dot sizes. The photoluminescence decay of the...

  • Growth of In0.25Ga0.75As quantum dots on GaP utilizing a GaAs interlayer. Stracke, G.; Glacki, A.; Nowozin, T.; Bonato, L.; Rodt, S.; Prohl, C.; Lenz, A.; Eisele, H.; Schliwa, A.; Strittmatter, A.; Pohl, U. W.; Bimberg, D. // Applied Physics Letters;11/26/2012, Vol. 101 Issue 22, p223110 

    Coherent In0.25Ga0.75As quantum dots (QDs) are realized on GaP(001) substrates by metalorganic vapor phase epitaxy in the Stranski-Krastanow mode utilizing a thin GaAs interlayer prior to In0.25Ga0.75As deposition. Luminescence is observed between 2.0 eV and 1.83 eV, depending on the thickness...

  • Thermal emission in type-II GaSb/GaAs quantum dots and prospects for intermediate band solar energy conversion. Hwang, Jinyoung; Martin, Andrew J.; Millunchick, Joanna M.; Phillips, Jamie D. // Journal of Applied Physics;Apr2012, Vol. 111 Issue 7, p074514 

    The electronic structure and thermal carrier capture and escape mechanisms are studied for GaSb/GaAs quantum dots with a type-II band alignment using admittance spectroscopy. Clear signatures are observed corresponding to confined quantum dot states with extracted activation energy of 0.337 eV...

  • Spectroscopic signature of strain-induced quantum dots created by buried InAs quantum dots in an InGaAs quantum well. Mazur, Yu. I.; Dorogan, V. G.; Marega, E.; Tarasov, G. G.; Salamo, G. J. // Journal of Applied Physics;Sep2011, Vol. 110 Issue 5, p054325 

    Spectroscopic study of self-assembled InAs/GaAs quantum dots (QDs) capped with an InxGa1-xAs quantum well (QW) is carried out under variable excitation intensity and temperature. The QW reduces strain in the QDs, and it is demonstrated that the cap layer shifts the transition energy of the QD...

  • Specific Features of Photoluminescence of InAs/GaAs QD Structures at Different Pumping Levels. Kulbachinskii, V. A.; Rogozin, V. A.; Lunin, R. A.; Belov, A. A.; Karuzskiĭ, A. L.; Perestoronin, A. V.; Zdoroveishchev, A. V. // Semiconductors;Nov2005, Vol. 39 Issue 11, p1308 

    Photoluminescence spectra of InAs/GaAs QD structures have been studied at different pumping powers and temperatures. At low pumping levels, one of the spectral lines in an undoped sample is shifted as the power increases. As the temperature increases, the luminescence intensity in the...

  • Temperature dependence of photoreflectance in InAs/GaAs quantum dots. Lai, C. M.; Chang, F. Y.; Chang, C. W.; Kao, C. H.; Lin, H. H.; Jan, G. J.; Lee, Johnson // Applied Physics Letters;6/2/2003, Vol. 82 Issue 22, p3895 

    Temperature dependent photoreflectance (PR) and photoluminescence experiments of the InAs/GaAs quantum dot (QD) structures were performed. At 20 K, effective band-gap transitions due to the InAs QDs, wetting layers, and GaAs buffer and cap layers were identified. Transition energies of the...

  • Optical properties of 1.3 μm InAs/GaAs bilayer quantum dots with high areal density. Ngo, C. Y.; Yoon, S. F.; Lim, D. R.; Wong, Vincent; Chua, S. J. // Applied Physics Letters;11/2/2009, Vol. 95 Issue 18, p181913 

    InAs/GaAs bilayer quantum dots (BQDs) are interesting structures for long wavelength emission due to its ability to tune the areal density and dot size separately. However, the need for two sets of growth rate and temperature for the respective QD layers complicates the growth procedures....

  • Characterization of excitonic features in self-assembled InAs/GaAs quantum dot superlattice structures via surface photovoltage spectroscopy. Chan, C. H.; Lee, C. H.; Huang, Y. S.; Wang, J. S.; Lin, H. H. // Journal of Applied Physics;5/15/2007, Vol. 101 Issue 10, p103102 

    This work systematically investigates the influence of InAs growth conditions and superlattice parameters on the optical properties of InAs/GaAs quantum dot (QD) superlattice structures grown by molecular beam epitaxy. Using surface photovoltage spectroscopy, one directly obtains the absorption...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics