Excitonic contribution of nanosilicon on light emitting properties
A phenomenological model is developed by integrating the effect of excitonic energy states, localized surface states and quantum confin ement (QC) to obtain an analytical expression for the room temperature photoluminescence (PL) intensity. We calculate the binding energy of strongly confined exc...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Published: |
2012
|
| Subjects: |
| _version_ | 1796859056642588672 |
|---|---|
| author | Ghoshal, Sib Krishna Sahar, Md. Rahim Rohani, M. S. |
| author_facet | Ghoshal, Sib Krishna Sahar, Md. Rahim Rohani, M. S. |
| author_sort | Ghoshal, Sib Krishna |
| collection | ePrints |
| description | A phenomenological model is developed by integrating the effect of excitonic energy states, localized surface states and quantum confin ement (QC) to obtain an analytical expression for the room temperature photoluminescence (PL) intensity. We calculate the binding energy of strongly confined excitons in silicon (Si) quantum dots (QD) having sizes 1 to 7.75 nm to examine its contribution on optical band gap and electronic properties. The band gap wit excitonic contribution is found to decrease as much as 0.23 eV for the smallest dot. The effect of exciton states explains almost accurately the experimental PL data. Our model provides the mechanism for controlling the PL intensity through fitting parameters. Huge excitonic effects, which depend strongly on QD size and shape, characterize the optical spectra. The results for the size dependence of the optical band gap, the PL int ensity, and oscillator strength are presented the role excitonic effects on optical and electronic properties are discussed. |
| first_indexed | 2024-03-05T19:21:32Z |
| format | Article |
| id | utm.eprints-46950 |
| institution | Universiti Teknologi Malaysia - ePrints |
| last_indexed | 2024-03-05T19:21:32Z |
| publishDate | 2012 |
| record_format | dspace |
| spelling | utm.eprints-469502017-09-27T04:14:42Z http://eprints.utm.my/46950/ Excitonic contribution of nanosilicon on light emitting properties Ghoshal, Sib Krishna Sahar, Md. Rahim Rohani, M. S. TA Engineering (General). Civil engineering (General) A phenomenological model is developed by integrating the effect of excitonic energy states, localized surface states and quantum confin ement (QC) to obtain an analytical expression for the room temperature photoluminescence (PL) intensity. We calculate the binding energy of strongly confined excitons in silicon (Si) quantum dots (QD) having sizes 1 to 7.75 nm to examine its contribution on optical band gap and electronic properties. The band gap wit excitonic contribution is found to decrease as much as 0.23 eV for the smallest dot. The effect of exciton states explains almost accurately the experimental PL data. Our model provides the mechanism for controlling the PL intensity through fitting parameters. Huge excitonic effects, which depend strongly on QD size and shape, characterize the optical spectra. The results for the size dependence of the optical band gap, the PL int ensity, and oscillator strength are presented the role excitonic effects on optical and electronic properties are discussed. 2012 Article PeerReviewed Ghoshal, Sib Krishna and Sahar, Md. Rahim and Rohani, M. S. (2012) Excitonic contribution of nanosilicon on light emitting properties. Advanced Materials Research, 364 . pp. 308-312. ISSN 1022-6680 http://dx.doi.org/10.4028/www.scientific.net/AMR.364.308 |
| spellingShingle | TA Engineering (General). Civil engineering (General) Ghoshal, Sib Krishna Sahar, Md. Rahim Rohani, M. S. Excitonic contribution of nanosilicon on light emitting properties |
| title | Excitonic contribution of nanosilicon on light emitting properties |
| title_full | Excitonic contribution of nanosilicon on light emitting properties |
| title_fullStr | Excitonic contribution of nanosilicon on light emitting properties |
| title_full_unstemmed | Excitonic contribution of nanosilicon on light emitting properties |
| title_short | Excitonic contribution of nanosilicon on light emitting properties |
| title_sort | excitonic contribution of nanosilicon on light emitting properties |
| topic | TA Engineering (General). Civil engineering (General) |
| work_keys_str_mv | AT ghoshalsibkrishna excitoniccontributionofnanosilicononlightemittingproperties AT saharmdrahim excitoniccontributionofnanosilicononlightemittingproperties AT rohanims excitoniccontributionofnanosilicononlightemittingproperties |