Binding energy of a hydrogenic donor impurity in an ellipsoidal finite‐potential quantum dot

In this article, the binding energy of a hydrogenic donor impurity in weakly oblate Ellipsoidal Quantum Dot (EQD), using the perturbation theory within the framework of effective mass approximation, is investigated. In this regard, the binding energies of 1S, 2S and 2P0 states for GaAs/Alx Ga1–x As structures, as functions of the dot radius and ellipticity constant, are calculated. Results show that variations of binding energies of a hydrogenic impurity with respect to the dot dimension are similar to the case of Spherical Quantum Dot (SQD). In addition, it is found that the binding energy is inversely proportional to the ellipticity constant. This behavior is more profound for 2P0 state, where, depending on the dot's dimensionality and ellipticity, the binding energy may become negative. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

[1]  J. R. Arthur,et al.  Molecular beam epitaxy , 1975 .

[2]  G. Bastard.  Hydrogenic impurity states in a quantum well: A simple model , 1981 .

[3]  G. Bastard.  Hydrogenic impurity states in a quantum well , 1982 .

[4]  S. Hersee,et al.  LOW-PRESSURE CHEMICAL VAPOR DEPOSITION , 1982 .

[5]  P. Dapkus.  Metalorganic Chemical Vapor Deposition , 1982 .

[6]  H. Spector,et al.  Hydrogen impurities in quantum well wires , 1986 .

[7]  Oliveira,et al.  Energy spectra of donors and acceptors in quantum-well structures: Effect of spatially dependent screening. , 1986, Physical review. B, Condensed matter.

[8]  Bajaj,et al.  Donor transition energies and their line strengths in GaAs/AlxGa , 1988, Physical review. B, Condensed matter.

[9]  Weber,et al.  Density of states and energy spectra of hydrogenic impurities in quantum-well wires. , 1988, Physical review. B, Condensed matter.

[10]  Porras-Montenegro,et al.  Hydrogenic impurities in GaAs-(Ga,Al)As quantum dots. , 1992, Physical review. B, Condensed matter.

[11]  Zhu,et al.  Spectrum and binding of an off-center donor in a spherical quantum dot. , 1994, Physical review. B, Condensed matter.

[12]  Y. Aoyagi,et al.  Observation of confinement-dependent exciton binding energy of GaN quantum dots , 1998 .

[13]  Antonio Puente,et al.  Orbital current mode in elliptical quantum dots , 1999 .

[14]  G. Iadonisi,et al.  Confined states in ellipsoidal quantum dots , 2000 .

[15]  W. R. Datars,et al.  Temperature dependence of the resistance of antimony nanowire arrays , 2001 .

[16]  E. Sadeghi,et al.  Study of the ordinary size effect in the electrical conductivity of Bi nanowires , 2001 .

[17]  K. Navaneethakrishnan,et al.  Donor binding energies and spin–orbit coupling in a spherical quantum dot , 2004 .

[18]  H. León,et al.  Excitonic and electronic states in ellipsoidal and semiellipsoidal quantum dots , 2005 .

[19]  A. Peter.  The effect of hydrostatic pressure on binding energy of impurity states in spherical quantum dots , 2005 .

[20]  Eduard M. Kazaryan,et al.  Electronic states in quantum dots with ellipsoidal symmetry , 2005 .