No data available.
Please log in to see this content.
You have no subscription access to this content.
No metrics data to plot.
The attempt to load metrics for this article has failed.
The attempt to plot a graph for these metrics has failed.
The full text of this article is not currently available.
Magneto-optical absorption in semiconducting spherical quantum dots: Influence of the dot-size, confining potential, and magnetic field
1. The origin of the lower dimensional systems dates back to 1957 when Schrieffer [J.R. Schrieffer, in: R.H. Kingston (Ed.), Semiconductor Surface Physics (University of Pennsylvania Press, Philadelphia, PA, 1957) p. 55] anticipated the quantization of energy levels in inversion layers. But the two-dimensional (2D) nature of electron gas – when only the lowest electric subband is occupied – was first confirmed experimentally by Fowler et al. [A.B. Fowler, F.F. Fang, W.E. Howard, P.J. Stiles, Phys. Rev. Lett. 16, 901 (1966)] in 1966.
2.For an extensive review of electronic, optical, and transport phenomena in the systems of reduced dimensions such as quantum wells, quantum wires, quantum dots, and (electrically/magnetically) modulated quantum systems, see, M.S. Kushwaha, Surf. Sci. Rep. 41, 1 (2001).
6.A. L. Efros and A. L. Efros, Sov. Phys.: Semiconductors 16, 772 (1982).
16.R. J. Warburton, C. Schaflein, D. Haft, F. Bickel, A. Lorke, K. Karrai, J. M. Garcia, W. Schoenfeld, and P. M. Petroff, Nature 405, 926 (2000).
41.D. Pines, The Many-Body Problem (Benjamin, New York, 1961);
41.A. L. Fetter and J. D. Walecka, Quantum Theory of Many-Particle Systems (McGraw-Hill, New York, 1971);
41.G. D. Mahan, Many Particle Physics (Plenum, New York, 1981).
45.L. J. Slater, Confluent Hypergeometric functions (Cambridge, London, 1960).
46.E. W. Hobson, The Theory of Spherical and Ellipsoidal Harmonics (Chelsea, New York, 1955).
47.H. A. Bethe and E. E. Salpeter, Quantum Mechanics of One- and Two-Electron Atoms (Academic Press, New York, 1957); See, e.g., the Appendix on Spherical Harmonics.
50.J. D. Jackson, Classical Electrodynamics (John Wily, New York, 1975).
53.J. K. Jain, Composite Fermions (Cambridge, New York, 2007).
Article metrics loading...
Semiconducting quantum dots – more fancifully dubbed artificial atoms – are quasi-zero dimensional, tiny, man-made systems with charge carriers completely confined in all three dimensions. The scientific quest behind the synthesis of quantum dots is to create and control future electronic and optical nanostructures engineered through tailoring size, shape, and composition. The complete confinement – or the lack of any degree of freedom for the electrons (and/or holes) – in quantum dots limits the exploration of spatially localized elementary excitations such as plasmons to direct rather than reciprocal space. Here we embark on a thorough investigation of the magneto-optical absorption in semiconducting spherical quantum dots characterized by a confining harmonic potential and an applied magnetic field in the symmetric gauge. This is done within the framework of Bohm-Pines’ random-phase approximation that enables us to derive and discuss the full Dyson equation that takes proper account of the Coulomb interactions. As an application of our theoretical strategy, we compute various single-particle and many-particle phenomena such as the Fock-Darwin spectrum; Fermi energy; magneto-optical transitions; probability distribution; and the magneto-optical absorption in the quantum dots. It is observed that the role of an applied magnetic field on the absorption spectrum is comparable to that of a confining potential. Increasing (decreasing) the strength of the magnetic field or the confining potential is found to be analogous to shrinking (expanding) the size of the quantum dots: resulting into a blue (red) shift in the absorption spectrum. The Fermi energy diminishes with both increasing magnetic-field and dot-size; and exhibits saw-tooth-like oscillations at large values of field or dot-size. Unlike laterally confined quantum dots, both (upper and lower) magneto-optical transitions survive even in the extreme instances. However, the intra-Landau level transitions are seen to be forbidden. The spherical quantum dots have an edge over the strictly two-dimensional quantum dots in that the additional (magnetic) quantum number makes the physics richer (but complex). A deeper grasp of the Coulomb blockade, quantum coherence, and entanglement can lead to a better insight into promising applications involving lasers, detectors, storage devices, and quantum computing.
Full text loading...
Most read this month