Theoretical Studies on the Effect of Confinement on Quantum Dots Using the Brus Equation

Download Download as PDF (Size:329KB)  HTML    PP. 96-100  
DOI: 10.4236/wjcmp.2012.22017    8,557 Downloads   15,927 Views   Citations


Quantum confinement effect in semiconductor quantum dots (QD's) of CdSe, ZnS and GaAs has been studied using the Brus Equation. It is found that the simple models obtained for the three different semiconductor nanocrystals exhibit the size dependence predicted by the particle-in-a-box model. The result shows that ground state confinement energy is inversely proportional to the size (radius). Thus, as one increases the radius (size), the confinement energy decreases, but never reaches zero. i.e., the lowest possible energy for the quantum dot sample is not zero.

Cite this paper

E. Chukwuocha, M. Onyeaju and T. Harry, "Theoretical Studies on the Effect of Confinement on Quantum Dots Using the Brus Equation," World Journal of Condensed Matter Physics, Vol. 2 No. 2, 2012, pp. 96-100. doi: 10.4236/wjcmp.2012.22017.


[1] M. A. Reed, E. S. Hornbeck, M. R. Deshpande, R. G. Wheeler, R. C. Bowen, J. N. Randal and W. R. Frensley, “Quantum Dots,” Scientific American, Vol. 268, No. 1, 1993, pp. 118-123. doi:10.1038/scientificamerican0193-118
[2] R. D Schaller and V. I. Klimov, “High Efficiency Carrier Multiplication in PbSe Nanocrystals: Implications for Solar Energy Conversion,” Physical Review Letters, Vol. 92, No. 18, 2004, pp. 186601-1-186601-4. doi:10.1103/PhysRevLett.92.186601
[3] C. Wang, M. Shim and P. Guyot-Sionnest, “Electrochromic Nanocrystal Quantum Dots,” Science, Vol. 291, No. 5512, 2001, pp. 2390-2392. doi:10.1126/science.291.5512.2390
[4] P. Martyniuk and A. Rogalski, “Quantum-Dot Infrared Photodetectors: Status and Outlook,” Progress in Quantum Electronics, Vol. 32, No. 3-4, 2008, pp. 89-120. doi:10.1016/j.pquantelec.2008.07.001
[5] A. A. Lagatsky, C. G. Leburn, C. T. A. Brown, W. Sibbett, S. A. Zolotovskaya and E. U. Rafailov, “Ultrashort-Pulse Lasers Passively Mode Locked by Quantum-Dot-Based Saturable Absorbers,” Progress in Quantum Electronics, Vol. 34, No. 1, 2010, pp. 1-45. doi:10.1016/j.pquantelec.2009.11.001
[6] J. Harbold and M. Plisch, “The Quantum Dot,” Cornell University, New York, 2008.
[7] O. Yoshitaka, “Solar Quest,” Nature Photonics Technology Conference, Tokyo, 19-21 October 2010.
[8] J. Sinclair and Dr. Dagotto, “An Introduction to Quantum Dots: Confinement, Synthesis, Artificial Atoms and Applications,” Solid State II Lecture Notes, University of Tennessee, Knoxville, 2009.
[9] P. Michler, “Single Quantum Dots: Fundamentals, Applications and New Concept, Physics and Astronomy Classification Scheme (PACS),” Springer-Verlag, Berlin, 2003.
[10] L. E. Brus, “Electron-Electron and Electron-Hole Interactions in Small Semiconductor Crystallites: The Size Dependence of the Lowest Excited Electronic State,” Journal of Chemical Physics, Vol. 80, No. 9, 1984, p. 4403. doi:10.1063/1.447218
[11] Y. Kayanuma, “Quantum-Size Effects of Interacting Electrons and Holes in Semiconductor Microcrystals with Spherical Shape,” Physical Review B, Vol. 38, No. 14, 1988, pp. 9797-9805. doi:10.1103/PhysRevB.38.9797
[12] J. Pan, A. Bahel, V. Mushti and M. V. Ramakrishna, “Chemistry of Nanoscale Semiconductor Clusters,” Chemical Physics, 1994, in press.
[13] T. Kippeny, L. A. Swafford and S. A. Rosnethal, “Semiconductor Nanocrystals: A Powerful Visual Aid for Introducing the Particle in a Box,” Journal of Chemical Education, Vol. 79, No. 9, 2002, pp. 1094-1100. doi:10.1021/ed079p1094
[14] L. E Brus, “A Simple Model for the Ionization Potential, Electron Affinity and Aqueous Redox Potentials of Small Semiconductor Crystallites,” Journal of Chemical Physics, Vol. 79, No. 11, 1983, pp. 5566-5571. doi:10.1063/1.445676
[15] J. M. Harbold, “The Electronic and Optical Properties of Colloidal Lead Selenide Semiconductor Nanocrysta,” Ph.D. Dissertation, Cornell University, New York, 2005.

comments powered by Disqus

Copyright © 2017 by authors and Scientific Research Publishing Inc.

Creative Commons License

This work and the related PDF file are licensed under a Creative Commons Attribution 4.0 International License.