Journal of Nanoparticle Research

, Volume 13, Issue 4, pp 1605–1612 | Cite as

Calculation of the quantum efficiency for the absorption on confinement levels in quantum dots

  • Vladimir Iancu
  • Mihai Razvan Mitroi
  • Ana-Maria Lepadatu
  • Ionel Stavarache
  • Magdalena Lidia CiureaEmail author
Research Paper


The quantum efficiency of the absorption on quantum confinement levels is investigated. This is achieved by modeling the electron confinement in a spherical quantum dot (QD). The confinement levels are calculated using both infinite and finite rectangular quantum wells. The spectral internal quantum efficiency is evaluated within both the models, by computing Einstein’s coefficients for the transitions between confinement levels. The size of QDs (1–3 nm radius) leads to negligible many body effects. The nature of the QD material and of the matrix embedding is taken into account in the finite rectangular quantum well approximation and introduces only a small correction. The temperature dependence of the efficiency is also taken into account. A numerical application is performed for a silicon QD of 2.5 nm radius, embedded in amorphous silica. It is proved that the absorption threshold shifts toward the far infrared limit and that the spectral internal quantum efficiency reaches 4–5% at the threshold.


Light absorption Quantum confinement Quantum dots Quantum efficiency Solar cells 



This work was supported from Project No. 471/2009 (ID 918/2008), Ideas Program, National Research, Development and Innovation Plan 2007–2013.


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Copyright information

© Springer Science+Business Media B.V. 2010

Authors and Affiliations

  • Vladimir Iancu
    • 1
  • Mihai Razvan Mitroi
    • 1
  • Ana-Maria Lepadatu
    • 2
  • Ionel Stavarache
    • 2
  • Magdalena Lidia Ciurea
    • 2
    Email author
  1. 1.“Politehnica” University of BucharestBucharestRomania
  2. 2.National Institute of Materials PhysicsMagureleRomania

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