TITLE

Excited-state dynamics and carrier capture in InGaAs/GaAs quantum dots

AUTHOR(S)
Zhang, L.; Boggess, Thomas F.; Gundogdu, K.; Flatte´, Michael E.; Deppe, D. G.; Cao, C.; Shchekin, O. B.
PUB. DATE
November 2001
SOURCE
Applied Physics Letters;11/12/2001, Vol. 79 Issue 20, p3320
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
Subpicosecond time-resolved photoluminescence upconversion is used to measure the 12 K first-excited-state dynamics in large InGaAs/GaAs self-assembled quantum dots designed for 1.3 μm diode lasers. A comparison with the ground-state dynamics suggests that energy relaxation occurs in a cascade through the multiple discrete levels with an average interlevel relaxation time of ∼250 fs. Excited-state emission is observed from two distinct populations. Due to the ultrafast relaxation from the excited state to the ground state in dots containing only a single exciton, the excited-state emission is dominated by the fraction of dots that capture more than one electron–hole pair. In this case, state filling in the ground state blocks the ultrafast relaxation channel, thereby enhancing the excited-state emission. While state filling and a random capture process dictate the primary features of the excited-state emission, at low excitation levels we find that the rise time of emission from the excited state is influenced by the much denser population of singly occupied dots. © 2001 American Institute of Physics.
ACCESSION #
5549490

 

Related Articles

  • Level degeneracy and temperature-dependent carrier distributions in self-organized quantum dots. Kim, K.; Norris, T. B.; Ghosh, S.; Singh, J.; Bhattacharya, P. // Applied Physics Letters;3/24/2003, Vol. 82 Issue 12, p1959 

    Using femtosecond three-pulse pump-probe spectroscopy, we investigated the transparency condition for the ground and first excited states in self-organized In[sub 0.4]Ga[sub 0.6]As quantum dots at different temperatures and wavelengths. The temperature-dependent behavior of the transparency...

  • Excited states in self-organized InAs/GaAs quantum dots: Theory and experiment. Grundmann, M.; Ledentsov, N.N. // Applied Physics Letters;2/12/1996, Vol. 68 Issue 7, p979 

    Examines the excited states of pyramidal-shaped indium arsenide/gallium arsenide quantum dots (QD) using calorimetric absorption spectroscopy and photoluminescence. Optical transitions involving the excited hole states and ground state transition of QD; Fabrication of QD using molecular beam...

  • InAs quantum-dot GaAs-based lasers grown on AlGaAsSb metamorphic buffers. Xin, Y.-C.; Vaughn, L. G.; Dawson, L. R.; Stintz, A.; Lin, Y.; Lester, L. F.; Huffaker, D. L. // Journal of Applied Physics;8/1/2003, Vol. 94 Issue 3, p2133 

    Self-assembled InAs quantum-dot lasers grown by molecular-beam epitaxy using an AlGaAsSb metamorphic buffer layer on a GaAs substrate are reported. The resulting quantum-dot ensemble has a density >3 × 10[sup 10]/cm² and a ground-state transition ranging from 1.46 to 1.63 µm. Pulsed,...

  • Widely tunable intersubband energy spacing of self-assembled InAs/GaAs quantum dots due to... Wang, X. C.; Xu, S. J. // Journal of Applied Physics;9/1/1999, Vol. 86 Issue 5, p2687 

    Presents information on a study which showed the reduction of energy spacing between ground state and excited state emissions from indium arsenide/gallium arsenide quantum dots due to interface interdiffusion induced by thermal treatment. Experimental details; Results and discussion.

  • Lateral intersubband photocurrent spectroscopy on InAs/GaAs quantum dots. Chu, L.; Zrenner, A.; Bo¨hm, G.; Abstreiter, G. // Applied Physics Letters;4/3/2000, Vol. 76 Issue 14 

    We report on lateral intersubband photocurrent spectroscopy on self-assembled InAs/GaAs quantum dots in normal incidence. The in-plane polarized intersubband transition between the first exited states and wetting layer in the conduction band is peaked at 180 meV with a spectral linewidth of 20...

  • Temperature-dependent modulation characteristics for 1.3 μm InAs/GaAs quantum dot lasers. Xu, Peng-Fei; Yang, Tao; Ji, Hai-Ming; Cao, Yu-Lian; Gu, Yong-Xian; Liu, Yu; Ma, Wen-Quan; Wang, Zhan-Guo // Journal of Applied Physics;Jan2010, Vol. 107 Issue 1, p013102 

    Temperature-dependent modulation characteristics of 1.3 μm InAs/GaAs quantum dot (QD) lasers under small signals have been carefully studied at various bias currents. Based on experimental observations, it is found that the modulation bandwidth significantly increases when excited state (ES)...

  • Observation of interdot energy transfer between InAs quantum dots. Nishibayashi, K.; Kawazoe, T.; Ohtsu, M.; Akahane, K.; Yamamoto, N. // Applied Physics Letters;7/28/2008, Vol. 93 Issue 4, p042101 

    We observed interdot excitation energy transfer between vertically aligned InAs quantum dots (QDs) separated by a 24-nm-thick spacer layer. This transfer was explained by resonant energy transfer via an optical near-field interaction between the first excited state of small QDs and the second...

  • Influence of p-doping on the temperature dependence of InAs/GaAs quantum dot excited state radiative lifetime. Harbord, Edmund; Iwamoto, S.; Arakawa, Y.; Spencer, P.; Clarke, E.; Murray, R. // Applied Physics Letters;10/29/2012, Vol. 101 Issue 18, p183108 

    The radiative lifetime of the excited state transition of undoped and p-doped InAs/GaAs quantum dots (QDs) is estimated from measurements of time-integrated and time-resolved luminescence from both ground and excited states. The radiative lifetime of the undoped QDs increases from 500 ps at 10 K...

  • Quantum correlation among photons from a single quantum dot at room temperature. Michler, P.; Imamoglu, A.; Mason, M. D.; Carson, P. J.; Strouse, G. F.; Buratto, S. K. // Nature;8/31/2000, Vol. 406 Issue 6799, p968 

    Presents a study on the quantum correlation among photons from a single quantum dot at room temperature. Use of Maxwell's equations to describe that statistical properties of fluorescence from an ensemble of atoms or semiconductors in one or more dimensions; Methods; Observation of photon...

Share

Read the Article

Courtesy of VIRGINIA BEACH PUBLIC LIBRARY AND SYSTEM

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

Try another library?
Sign out of this library

Other Topics