Theoretical Study on the Absorbance Bandgap of the Group II-VI Semiconductor Quantum Dots

  IJRES-book-cover  International Journal of Recent Engineering Science (IJRES)          
  
© 2024 by IJRES Journal
Volume-11 Issue-4
Year of Publication : 2024
Authors : O. K. Asielue, O. K. Okongwu, A. O. Ojobeagu, S. C. Igbokwe, H. I. Ikeri, E. E. Okechukwu Nwuke, V. M. Adokor
DOI : 10.14445/23497157/IJRES-V11I4P104

How to Cite?

O. K. Asielue, O. K. Okongwu, A. O. Ojobeagu, S. C. Igbokwe, H. I. Ikeri, E. E. Okechukwu Nwuke, V. M. Adokor, "Theoretical Study on the Absorbance Bandgap of the Group II-VI Semiconductor Quantum Dots," International Journal of Recent Engineering Science, vol. 11, no. 4, pp. 27-30, 2024. Crossref, https://doi.org/10.14445/23497157/IJRES-V11I4P104

Abstract
A theoretical study on the absorbance bandgap of the CdSe, CdS and ZnS QDs has been studied using effective mass approximation. The results strongly indicate that the quantum confinement effect on QDs leads to a size-dependent increase in the absorbance bandgap. This property allows for the tuning of optical and electronic characteristics, making these materials highly valuable in various advanced technological applications. It is found that CdSe with a bulk bandgap of ~1.7 eV increases as the dot size decreases, resulting in a shift from red to blue emission; CdS begins at ~2.42 eV and increases as the size decreases, shifting from green to violet emission and ZnS with largest initial bandgap of ~3.68 eV is pushed further into the UV range as the size decreases. Thus, by controlling the size of the QDs, it is possible to precisely tailor their properties for specific uses, making them highly versatile for a range of applications in optoelectronics, biomedical imaging, and quantum computing.

Keywords
Absorbance spectrum, Bandgap, Quantum confinement, Quantum dot, Effective mass approximation.

Reference
[1] L.E. Brus, “Electron-Electron and Electron-Hole Interactions in Small Semiconductor. Crystallites: The Size Dependence of The Lowest Excited Electronic State,” The Journal of Chemical Physics, vol. 80, no. 9, pp. 4403-4409, 1984.
[CrossRef] [Google Scholar] [Publisher Link]
[2] S.T. Harry, and M.A. Adekanmbi, “Confinement Energy of Quantum Dots and the Brus Equation,” International Journal of Research - Granthaalayah, vol. 8, no. 11, pp. 318-323, 2020.
[CrossRef] [Google Scholar] [Publisher Link]
[3] Ladislaus Alexander Banyai, and Stephan W Koch, Semiconductor Quantum Dots, World Scientific Series on Atomic, Molecular and Optical Physics, vol. 2, pp. 1-256, 1993.
[CrossRef] [Google Scholar] [Publisher Link]
[4] A.J. Nozik et al., “Size Quantization in Small Semiconductor Particles,” Journal of Physical Chemistry, vol. 89, no. 3, pp. 397-399, 1985.
[CrossRef] [Google Scholar] [Publisher Link]
[5] Ephrem O. Chukwuocha, Michael C. Onyeaju, and Taylor S. 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, pp. 96-100, 2012.
[CrossRef] [Google Scholar] [Publisher Link]
[6] John H. Davies, The Physics of Low-Dimensional Semiconductors: An Introduction, Cambridge University Press, 1997.
[CrossRef] [Google Scholar] [Publisher Link]
[7] Madan Singh, Monika Goyal, and Kamal Devlal, “Size and Shape Effects on The Band Gap of Semiconductor Compound Nanomaterials,” Journal of Taibah University for Science, vol. 12, no. 4, pp. 470-475, 2018.
[CrossRef] [Google Scholar] [Publisher Link]
[8] Cherie R. Kagan et al., “Building Devices from Colloidal Quantum Dots,” Science, vol. 353, no. 6302, 2016.
[CrossRef] [Google Scholar] [Publisher Link]
[9] M.G. Bawendi, M.L. Steigerwald, and L.E. Brus, “The Quantum Mechanics of Larger Semiconductor Clusters (“Quantum Dots”),” Annual Review of Physical Chemistry, vol. 41, pp. 477-496, 1990.
[CrossRef] [Google Scholar] [Publisher Link]
[10] Nisha Pandey, Amrita Dwivedi, and Arunendra Patel, “Theoretical Study of Dependence of Wavelength on Size of Quantum Dot,” International Journal for Scientific Research and Development, vol. 4, no. 1, pp. 1158-1159, 2016.
[Google Scholar] [Publisher Link]