Abstract
Theoretical investigations of electronic structure of quantum dots is of current interest in nanophase materials. Empirical theories such as effective mass approximation, tight binding methods and empirical pseudo-potential method are capable of explaining the experimentally observed optical properties. We employ the empirical pseudo-potential to calculate the gap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) as a function of shape and size of the quantum dots. Our studies explain the building up of the bulk band structure when the size of the dot is much larger than the bulk Bohr exciton radius. We present our investigations of HOMO-LUMO gap variation with size, for CdSe, ZnSe and GaAs quantum dots. The calculated excitonic energies are sensitive to the shape and size of quantum dots and are in good agreement with experimental HOMO-LUMO gaps for CdSe quantum dots. The agreement improves as experimentally observed lattice contraction is incorporated in pseudo-potential calculations for ZnSe quantum dots. Electronic structure evolution, as the size of quantum dot increases, is presented for CdSe, ZnSe and GaAs quantum dots.
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References
Bowen Katari J E, Colvin V L and Alivisatos A P 1994 J. Phys. Chem. 98 4109
Brus L E 1983 J. Chem. Phys. 79 5566
Brus L E 1984 J. Chem. Phys. 80 4403
Chestnoy N, Hull R and Brus L E 1987 J. Chem. Phys. 85 2237
Cohen M L and Heine V 1970 Solid state physics (eds) H Eherenreich et al (New York: Academic Press) Vol. 24, p. 37
Cohen M L and Chelikowsky J R 1989 Electronic structure and optical properties of semiconductors (Berlin: Springer-Verlag)
Cohen M L and Bergstresser T K 1966 Phys. Rev. 141 789
Colvin V L, Schlamp M C and Alivisatos A P 1994 Nature 370 354
Dance I G, Choy A and Shudder M L 1984 J. Am. Chem. Soc. 106 6285
Éfros Al L and Éfros A L 1982 Sov. Phys. Semicond. 16 772
Eichkorn K and Ahlrichs R 1998 Chem. Phys. Lett. 288 235
Harrison W A 1966 Pseudopotentials in the theory of metals (New York: Benjamin)
Hartmann H, Mach R and Selle B 1982 Current topics in materials science (ed.) E Kaldis (Amsterdam: North-Holland Pub. Co.) 9
Hines H and Guyot-Sionnest P 1998 J. Phys. Chem. B102 3655
Joswig Jan-Ole, Springborg M and Seifert G 2000 J. Phys. Chem. B104 2617
Kayanuma Y 1988 Phys. Rev. B38 9797
Kayanuma Y and Momiji H 1990 Phys. Rev. B41 10261
Kumbhojkar N 2002 Studies of size dependence of electronic structure of semiconducting quantum dots, Ph.D. Thesis, University of Pune, Pune
Kumbhojkar N and Kshirsagar A 2001a Proceedings of national conference on ’science and technology of nanomaterials and clusters’ (New Delhi: Allied Publishers Limited)
Kumbhojkar N and Kshirsagar A 2001b in Science and technology of nano-structured materials (eds) B K Rao et al (NY: Nova Publishers)
Kumbhojkar N, Mahamuni S, Leppert V and Risbud S H 1997 Nanostruct. Mater. 10 117
Kumbhojkar N, Nikesh V V, Kshirsagar A and Mahamuni S 2000 J. Appl. Phys. 88 6260
Kuno M, Lee J K, Dabbousi B O, Mikulec F V and Bawendi M G 1997 J. Chem. Phys. 106 9869
Lee In-Ho, Kim Yong-Hoon and Ann Kang-Hun 2001 J. Phys.: Condens. Matter 13 1987
Leppert V, Mahamuni S, Kumbhojkar N and Risbud S H 1997a Mater. Sci. Eng. B52 89
Leppert V, Risbud S H and Fendrof M 1997b Philos. Mag. Lett. 75 29
Leung K, Pokrant S and Whaley K B 1998 Phys. Rev. B57 12291
Lippens P E and Lannoo M 1989 Phys. Rev. B39 10935
Malik M A, O’Brien P, Noragev S and Smith J 2003 J. Mater. Chem. 13 2591
Matxain J M, Irigoras A, Fowler J E and Ugalde J M 2001 Phys. Rev. A63 13202
Matxain J M, Irigoras A, Fowler J E and Ugalde J M 2001 64 13201
Murray C B, Nirmal N, Norris D J, Bawendi M G and Shank C V 1993 Z. Phys. D26 231
Murray C B, Norris D J and Bawendi M G 1993 J. Am. Chem. Soc. 115 8706
Nair S V, Sinha S and Rustagi K C 1987 Phys. Rev. B35 4098
Nair S V, Ramaniah L M and Rustagi K C 1992 Phys. Rev. B45 5969
Nosaka Y 1991 J. Phys. Chem. 95 5054
Olshavsky M A, Goldstein A N and Alivisatos A P 1990 J. Am. Chem. Soc. 112 9438
Pickett W E 1989 Comput. Phys. Rep. 9 115 and references therein
Pokrant S and Whaley K B 1999 Eur. Phys. J. D6 255
Ramaniah L M and Nair S V 1993 Phys. Rev. B47 7132
Ramaniah L M and Nair S V 1995 Physica B212 245
Rama Krishna M V and Friesner R A 1991a J. Chem. Phys. 95 8309
Rama Krishna M V and Friesner R A 1991b Phys. Rev. Lett. 67 629
Rama Krishna M V and Friesner R A 1992 J. Chem Phys. 96 873
Robbles J, Mayorga O, Lee T and Diaz D 1999 Nanostruct. Mater. 11 283
Rogach A L, Kornowski A, Gao M, Echyüller A E and Weller H 1999 J. Phys. Chem. B103 3065
Ruppin R 1989 J. Phys. Chem. Solids 50 877
Sapra S and Sarma D D 2004 Phys. Rev. B69 125304
Schiff L I 1968 Quantum mechanics (Tokyo: McGraw-Hill Ltd.) p. 39
Sercel C and Vahala K J 1990 Phys. Rev. B42 3690
Shim M and Phillippe Guyot-Sionnest 1999 J. Chem. Phys. 11 6955
Slater J C and Koster G F 1954 Phys. Rev. 94 1498
Tran Thoi D B, Hu Y Z and Koch S W 1990 Phys. Rev. B42 11261
Troparevsky M Claudia and Chelikowsky J R 2001 J. Chem. Phys. 114 943
Vasiliev I, Ögüt S and Chelikowsky J R 1999 Phys. Rev. B60 R8477
Viswanatha R, Sapra S, Saha-Dasgupta T and Sarma D D 2005 Phys. Rev. B72 045333
Vossmeyer T, Katsikas L, Giersig M, Popovic I G, Diesner K, Chemseddine A, Eychmuller A and Weller H 1994 J. Phys. Chem. 98 7665
Wang Y and Herron N 1990a J. Phys. Chem. 92 4988
Wang Y and Herron N 1990b Phys. Rev. B42 7253
Yoffe A D 1993 Adv. Phys. 42 173 and references therein
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Kshirsagar, A., Kumbhojkar, N. Empirical pseudo-potential studies on electronic structure of semiconducting quantum dots. Bull Mater Sci 31, 297–307 (2008). https://doi.org/10.1007/s12034-008-0048-7
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DOI: https://doi.org/10.1007/s12034-008-0048-7