COLL 398 |
| X. B. Zhang1, J. H. Ryou1, G. Walter2, N. Holonyak2, and R. D. Dupuis1. (1) School of Electric and Computer Engineering, Georgia Institute of Technology, Atlanta, GA 30332, (2) Micro and Nanotechnology Laboratory, The University of Illinois at Urbana-Champaign, Urbana, IL 61801 |
| We present the cathodoluminescence (CL) data of several InP quantum dot (QD)-based heterostructures grown by metalorganic chemical vapor deposition on (001) GaAs substrates. The structures include: (1) InP/InAlGaP quantum dots (QDs) with Si doping in a layer adjacent to the QD layer; (2) InP QDs coupled with an InGaP quantum well (QW) through a thin InAlGaP barrier (the so-called QW+QD structure); and (3) QW+QD structures with Si doping in a layer close to the QW layer. We show that for structures in (1), the CL intensity of InP QDs increases significantly when Si doping is introduced; for QW+QD structures, unlike the QD structures or InP bulk material, the emission energy of QDs is quite insensitive to temperature; for structures in (3), emission from QDs is blocked when the InAlGaP barrier in between the QW and QD layers is thick but is strongly enhanced when the barrier is thin. The underlying mechanism of the observed CL properties is discussed. |
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Nanoscience and Nanotechnology
8:30 AM-11:45 AM, Wednesday, March 31, 2004 Marriott -- Orange County 5, Oral
Division of Colloid and Surface Chemistry |