Pramana

, 90:57 | Cite as

Exciton binding energy in a pyramidal quantum dot

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Abstract

The effects of spatially dependent effective mass, non-parabolicity of the conduction band and dielectric screening function on exciton binding energy in a pyramid-shaped quantum dot of GaAs have been investigated by variational method as a function of base width of the pyramid. We have assumed that the pyramid has a square base with area \(a\times a\) and height of the pyramid \(H=a/2\). The trial wave function of the exciton has been chosen according to the even mirror boundary condition, i.e. the wave function of the exciton at the boundary could be non-zero. The results show that (i) the non-parabolicity of the conduction band affects the light hole (lh) and heavy hole (hh) excitons to be more bound than that with parabolicity of the conduction band, (ii) the dielectric screening function (DSF) affects the lh and hh excitons to be more bound than that without the DSF and (iii) the spatially dependent effective mass (SDEM) affects the lh and hh excitons to be less bound than that without the SDEM. The combined effects of DSF and SDEM on exciton binding energy have also been calculated. The results are compared with those available in the literature.

Keywords

Pyramid quantum dot dielectric screening function spatially dependent effective mass exciton GaAs non-parabolicity 

PACS Nos

73.63.Kv 77.22.Ch 78.66.−w 

Notes

Acknowledgements

The authors thank the University Grants Commission (UGC), New Delhi, India, for the financial support through Major Research Project (No.F.42-836 / 2013(SR) dated 22.3.2013) and the authorities of Jayaraj Annapackiam College for Women (Autonomous), Periyakulam, Theni District, Tamil Nadu, India, for the encouragements.

References

  1. 1.
    S Mosleni-Tabrizi, Eigenstate calculations for multidimensional nanostructures: Quantum wells, wires and dot (VDM Verlag Dr. Muller Aktiengesellschaft & Co.KG, Germany, 2008)Google Scholar
  2. 2.
    E Kasapoglu and I Sokmen, Physica E  27, 198 (2005)ADSCrossRefGoogle Scholar
  3. 3.
    S Wu, Physica B  406, 4634 (2011)ADSCrossRefGoogle Scholar
  4. 4.
    N Elmeshad, H Abdelhamid, H Hassanein, S Abdelmota and S Said, Chin. J. Phys.  47, 92 (2009)Google Scholar
  5. 5.
    Z Xiao, J. Appl. Phys.  86, 4509 (1999)ADSCrossRefGoogle Scholar
  6. 6.
    A Taqi and J Diouri, Semicond. Phys. Quantum Electron. Optoelectron.  15, 365 (2012)CrossRefGoogle Scholar
  7. 7.
    B Sukumar and K Navaneethakrishnan, Solid State Commun.  76, 561 (1990)ADSCrossRefGoogle Scholar
  8. 8.
    H Akbas, S Aktas, S E Okan and M Ulas, Solid State Commun.  23, 113 (1998)Google Scholar
  9. 9.
    Z Y Deng, J K Guo and T R Lai, Phys. Rev. B  50, 5736 (1994)ADSCrossRefGoogle Scholar
  10. 10.
    X H Qi, X J Kong and J J Liu, Phys. Rev. B  58, 10578 (1998)ADSCrossRefGoogle Scholar
  11. 11.
    A J Peter and K Navaneethakrishnan, Physica E  40, 2747 (2008)ADSCrossRefGoogle Scholar
  12. 12.
    S Nomura and T Kobayashi, Solid State Commun.  78, 677 (1991)ADSCrossRefGoogle Scholar
  13. 13.
    N Schildermans, M Hayne, V V Moshchalkov, A Rastelli and O G Schmidt, Phys. Rev. B  72, 115312 (2005)ADSCrossRefGoogle Scholar
  14. 14.
    Y Sidor, B Partoens, F M Peeters, J Maes, M Hayne, D Fuster, Y Gonzalez, L Gonzalez and V V Moshchalkov, Phys. Rev. B  76, 195320 (2007)ADSCrossRefGoogle Scholar
  15. 15.
    L C Andreani and A Pasquarello, Phys. Rev. B  42, 8928 (1990)ADSCrossRefGoogle Scholar
  16. 16.
    U Ekenberg and M Altarelli, Phys. Rev. B  35, 7585 (1987)ADSCrossRefGoogle Scholar
  17. 17.
    V Lozovski and V Piatnytsia, J. Comput. Theor. Nanosci.  8, 2335 (2011)CrossRefGoogle Scholar
  18. 18.
    Y Vorobiev, V Vieira, P Ribeiro, V Gorley, P Horley, J G Hernandez and T Torchynska, Recent Researches in Communications, Automation, Signal Processing, Nanotechnology, Astronomy and Nuclear Physics, 127 (WSEAS Press, 2011)Google Scholar
  19. 19.
    Yu V Vorobiev, T V Torchynska and P P Horley, Physica E  51, 42 (2013)ADSCrossRefGoogle Scholar
  20. 20.
    M Grundmann, O Stier and D Bimberg, Phys. Rev. B  52, 11969 (1995)ADSCrossRefGoogle Scholar
  21. 21.
    M A Borji, A Reyahi, E Rajaei and M Ghahremani, Pramana – J. Phys.,  https://doi.org/10.1007/s12043-017-1424-x (2017)
  22. 22.
    K Jayakumar, S Balasubramanian and M Tomak, Phys. Rev. B  33, 4002 (1986)ADSCrossRefGoogle Scholar
  23. 23.
    M Arulmozhi and S Balasubramanian, Phys. Rev. B  51, 2592 (1995)ADSCrossRefGoogle Scholar

Copyright information

© Indian Academy of Sciences 2018

Authors and Affiliations

  1. 1.Department of PhysicsMother Teresa Women’s UniversityKodaikanal India
  2. 2.Department of PhysicsJayaraj Annapackiam College for Women (Autonomous)Periyakulam,Theni District India

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