2009
Cruz-Irisson, Miguel; Wang, Chu Min
Electronic and Vibrational Properties of Porous Silicon Artículo de revista
En: Journal of Nano Research, vol. 5, pp. 153–160, 2009.
Resumen | Enlaces | BibTeX | Etiquetas: Porous Silicon (PS), Raman scattering, Tight Binding
@article{cruz-irisson2009,
title = {Electronic and Vibrational Properties of Porous Silicon},
author = {Miguel Cruz-Irisson and Chu Min Wang},
doi = {10.4028/www.scientific.net/JNanoR.5.153},
year = {2009},
date = {2009-01-01},
urldate = {2009-01-01},
journal = {Journal of Nano Research},
volume = {5},
pages = {153\textendash160},
abstract = {For ordered porous silicon, the Born potential and phonon Green’s functions are used to investigate its Raman response, while the electronic band structure and dielectric function are studied by means of a sp3s* tight-binding supercell model, in which periodical pores are produced by removing columns of atoms along [001] direction from a crystalline Si structure and the pores surfaces are passivated by hydrogen atoms for the electronic band structure calculations. This supercell model emphasizes the interconnection between silicon nanocrystals, delocalizing the electronic and phononic states. However, the results of both elementary excitations show a clear quantum confinement signature, which is contrasted with that of nanowire systems. In addition, ab-initio calculations of small supercells are performed in order to verify the tight-binding results. The calculated dielectric function is compared with experimental data. Finally, a shift of the highest-frequency Raman peak towards lower energy is observed, in agreement with the experimental data.},
keywords = {Porous Silicon (PS), Raman scattering, Tight Binding},
pubstate = {published},
tppubtype = {article}
}
For ordered porous silicon, the Born potential and phonon Green’s functions are used to investigate its Raman response, while the electronic band structure and dielectric function are studied by means of a sp3s* tight-binding supercell model, in which periodical pores are produced by removing columns of atoms along [001] direction from a crystalline Si structure and the pores surfaces are passivated by hydrogen atoms for the electronic band structure calculations. This supercell model emphasizes the interconnection between silicon nanocrystals, delocalizing the electronic and phononic states. However, the results of both elementary excitations show a clear quantum confinement signature, which is contrasted with that of nanowire systems. In addition, ab-initio calculations of small supercells are performed in order to verify the tight-binding results. The calculated dielectric function is compared with experimental data. Finally, a shift of the highest-frequency Raman peak towards lower energy is observed, in agreement with the experimental data.
2003
Guzmán, D.; Corona, U.; Cruz, M.
Electronic states and optical properties of silicon nanocrystals Artículo de revista
En: Journal of Luminescence, vol. 102-103, pp. 487-491, 2003, ISSN: 0022-2313, (Proceedings of the 2002 International Conference on Luminescence and Optical Spectroscopy of Condensed Matter).
Resumen | Enlaces | BibTeX | Etiquetas: Dielectric constant, Silicon nanocrystals, Tight Binding
@article{GUZMAN2003487,
title = {Electronic states and optical properties of silicon nanocrystals},
author = {D. Guzm\'{a}n and U. Corona and M. Cruz},
url = {https://www.sciencedirect.com/science/article/pii/S0022231302005872},
doi = {https://doi.org/10.1016/S0022-2313(02)00587-2},
issn = {0022-2313},
year = {2003},
date = {2003-01-01},
urldate = {2003-01-01},
journal = {Journal of Luminescence},
volume = {102-103},
pages = {487-491},
abstract = {Photoluminescence properties of nanometer Si-based materials have motivated a great deal of experimental and theoretical research effort because they exhibit favourable applications in opto-electronic devices. The quantum confinement effect of photoexcited carriers within nanocrystallites was mainly proposed to be responsible for the visible luminescence from these materials. In this work, the electronic states and optical transition properties of Si nanocrystals are studied by means of an sp3s* semiempirical tight-binding approximation and supercell model, in which the silicon nanocrystals are columns of square cross-section with width from a to 7a, where a is the lattice constant. The calculations have been carried out for light polarized in the [100] direction, i.e., perpendicular to the wire alignment. We present the dependence of the imaginary part of the dielectric function on the quantum confinement within two different schemes, which are applied and compared.},
note = {Proceedings of the 2002 International Conference on Luminescence and Optical Spectroscopy of Condensed Matter},
keywords = {Dielectric constant, Silicon nanocrystals, Tight Binding},
pubstate = {published},
tppubtype = {article}
}
Photoluminescence properties of nanometer Si-based materials have motivated a great deal of experimental and theoretical research effort because they exhibit favourable applications in opto-electronic devices. The quantum confinement effect of photoexcited carriers within nanocrystallites was mainly proposed to be responsible for the visible luminescence from these materials. In this work, the electronic states and optical transition properties of Si nanocrystals are studied by means of an sp3s* semiempirical tight-binding approximation and supercell model, in which the silicon nanocrystals are columns of square cross-section with width from a to 7a, where a is the lattice constant. The calculations have been carried out for light polarized in the [100] direction, i.e., perpendicular to the wire alignment. We present the dependence of the imaginary part of the dielectric function on the quantum confinement within two different schemes, which are applied and compared.
