Showing posts with label J. Bhattacharyya. Show all posts
Showing posts with label J. Bhattacharyya. Show all posts

Monday, February 29, 2016

Abstract-Inter-sublevel dynamics in single InAs/GaAs quantum dots induced by strong terahertz excitation




We combine micro-photoluminescence(PL) with terahertz excitation to investigate the response of singleself-assembled InAs/GaAs quantum dots to intense terahertz pulses tuned to the s-to-p transition. Spectra and transients of single photoluminescence lines reveal the dynamics of electrons upon excitation and subsequent relaxation back into the initial state. Under certain circumstances, the terahertz pulse can release trapped charge carriers, which relax into the quantum dot. Furthermore, we demonstrate near-total depletion of the positive trionPL by an intense terahertz pulse.

Monday, March 31, 2014

Abstract-Magnetic control of Coulomb scattering and terahertz transitions among excitons


J. Bhattacharyya, S. Zybell, F. Eßer, M. Helm, H. Schneider, L. Schneebeli, C. N. Böttge, B. Breddermann, M. Kira, S. W. Koch, A. M. Andrews, and G. Strasser

http://journals.aps.org/prb/abstract/10.1103/PhysRevB.89.125313
Time-resolved terahertz quenching studies of the magnetoexcitonic photoluminescence from GaAs/AlGaAs quantum wells are performed. A microscopic theory is developed to analyze the experiments. Detailed experiment-theory comparisons reveal a remarkable magnetic-field controllability of the Coulomb and terahertz interactions in the excitonic system.
DOI: http://dx.doi.org/10.1103/PhysRevB.89.125313
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  • Published 31 March 2014
  • Received 23 September 2013
  • Revised 11 March 2014
©2014 American Physical Society

Wednesday, September 25, 2013

Abstract-Magnetic control of Coulomb scattering and terahertz transitions among excitons





Time-resolved terahertz quenching studies of the magnetoexcitonic photoluminescence from GaAs/AlGaAs quantum wells are performed. A microscopic theory is developed to analyze the experiments. Detailed experiment-theory comparisons reveal a remarkable magnetic-field controllability of the Coulomb and terahertz interactions in the excitonic system.