TITLE

Effect of Si delta doping on the luminescence properties of InP/InAlP quantum dots

AUTHOR(S)
Zhang, X. B.; Heller, R. D.; Noh, M. S.; Dupuis, R. D.; Walter, G.; Holonyak, N.
PUB. DATE
June 2003
SOURCE
Applied Physics Letters;6/16/2003, Vol. 82 Issue 24, p4343
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
We show that the cathodoluminescence (CL) properties of InP quantum dots (QDs) grown on In[SUB0.5]Al[SUB0.5]P matrix layers, lattice-matched to (001) GaAs substrates, can be greatly improved by introducing silicon delta doping in the layer adjacent to the QDs. Under optimized conditions, the room-temperature CL intensity of QDs can be improved by ∼16 times. We speculate that the increased CL intensity is caused by the efficient capture of electrons from the reservoir of the delta-doped layer into the QDs, which, to some extent, counterbalances the thermal escape of electrons from the QDs. A temperature-dependent CL study of InP QDs grown without Si delta doping shows a quenching of the CL at high temperatures, which supports the unipolar escape of electrons from QDs, while delta-doped QDs show an anomalous behavior. The QD integrated CL intensity increases with temperature and then decreases after 200 K. This anomalous behavior is interpreted as caused by competition between two processes: (1) thermal activation of carriers out of the potential well introduced by delta doping and then capture by QDs, which enhances the CL intensity; and (2) quenching of the CL due to thermal activation of carriers out of the QDs.
ACCESSION #
9987373

 

Related Articles

  • Determination of nonradiative surface layer thickness in quantum dots etched from single quantum well GaAs/AlGaAs. Clausen, E. M.; Craighead, H. G.; Worlock, J. M.; Harbison, J. P.; Schiavone, L. M.; Florez, L.; Van der Gaag, B. // Applied Physics Letters;10/2/1989, Vol. 55 Issue 14, p1427 

    Low-temperature cathodoluminescence spectroscopy was used to investigate the luminescence efficiency of reactive ion etched quantum dots, varying in diameter from 200 μm down to 60 nm. The luminescence efficiency was found to be degraded both with decreasing nanostructure size and with...

  • Cathodoluminescence wavelength imaging of μm-scale energy variations in InAs/GaAs self-assembled quantum dots. Rich, D. H.; Rich, D.H.; Zhang, C.; Mukhametzhanov, I.; Madhukar, A. // Applied Physics Letters;6/12/2000, Vol. 76 Issue 24 

    Cathodoluminescence wavelength imaging of InAs/GaAs self-assembled quantum dots (SAQDs) was performed to study the spatial variation in the spectral line shape of the broadened quantum dot (QD) ensemble. The line shape was found to vary on a scale of ∼μm, revealing attendant variations...

  • Many-particle effects in Ge quantum dots investigated by time-resolved capacitance spectroscopy. Kapteyn, C. M. A.; Kapteyn, C.M.A.; Lion, M.; Heitz, R.; Bimberg, D.; Miesner, C.; Asperger, T.; Brunner, K.; Abstreiter, G. // Applied Physics Letters;12/18/2000, Vol. 77 Issue 25 

    Hole emission from self-organized Ge quantum dots with a diameter of ∼70 nm in a Si matrix is investigated by time-resolved capacitance spectroscopy [deep level transient spectroscopy (DLTS)]. A complex DLTS signal is observed and explained in terms of thermally activated emission from...

  • Spectroscopy of a silicon quantum dot. Khoury, M.; Rack, M. J. // Applied Physics Letters;3/15/1999, Vol. 74 Issue 11, p1576 

    Studies the spectroscopy of a silicon quantum dot. Use of a silicon quantum dot embedded in a metal-oxide-semiconductor field-effect transistor structure; Depletion of the quasi-two-dimensional electron gas.

  • Electronic structure and compositional interdiffusion in self-assembled Ge quantum dots on Si(001). Seok, J. H.; Kim, J. Y. // Applied Physics Letters;5/14/2001, Vol. 78 Issue 20, p3124 

    The radiative recombination peaks over a broad energy range of 0.75-0.9 eV have been observed by photoluminescence spectroscopy in self-assembled Ge/Si quantum dot structures. In order to clarify the broadness of the peak distribution, we have investigated the electronic structure of an...

  • Silicon single-electron quantum-dot transistor switch operating at room temperature. Zhuang, Lei; Guo, Lingjie; Chou, Stephen Y. // Applied Physics Letters;3/9/1998, Vol. 72 Issue 10 

    We fabricated a silicon single-electron quantum-dot transistor, which showed drain current oscillations at room temperature. These oscillations are attributed to electron tunneling through a single silicon quantum dot inside a narrow wire channel. Analysis of its current–voltage...

  • Influence of the wetting-layer growth kinetics on the size and shape of Ge self-assembled quantum dots on Si(001). Kim, H. J.; Xie, Y. H. // Applied Physics Letters;7/9/2001, Vol. 79 Issue 2 

    The growth temperature of the wetting layer is used as the key variable in the study of a series of Ge self-assembled quantum dots on Si(001) substrates. A relaxed SiGe buffer layer is used for most of the samples as a means of maintaining the density of Ge dots. Ge dots are in the shapes of...

  • Dependence of the Optical Gap of Si Quantum Dots on the Dot Size. Burdov, V. A. // Semiconductors;Oct2002, Vol. 36 Issue 10, p1154 

    The dependence of the optical gap of Si quantum dots, embedded in a SiO[sub 2] insulator host, on the dot size was calculated in terms of an envelope-function approximation. It is shown that consideration of the finiteness of the SiO[sub 2] band gap and an abrupt change in the effective mass at...

  • Single hole quantum dot transistors in silicon. Leobandung, Effendi; Lingjie Guo // Applied Physics Letters;10/16/1995, Vol. 67 Issue 16, p2338 

    Presents a single hole quantum dot transistors in silicon. Observation of strong oscillations in the drain current; Value of the average energy level spacing; Fraction of the energy level spacing coming from the Coulomb interaction between holes.

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