Polarization Spectroscopy of an Isolated Quantum Dot and an Isolated Quantum Wire
Photoluminescence spectra of an isolated GaAs quantum dot within an AlGaAs quantum wire are studied. The examination of behavior of spectra in a magnetic field provided an opportunity to estimate the exciton binding energy in the quantum dot, which turned out to be 10 times higher than the bulk exciton binding energy in GaAs. It is demonstrated that the signal of exciton photoluminescence from the quantum dot emitted along the nanowire axis is linearly polarized. At the same time, the photoluminescence signal propagating in the direction perpendicular to the nanowire axis is almost unpolarized. This may be attributed to the nonaxial dot positioning in the wire under a giant increase in the binding energy of an exciton affected by an image potential.
V.P. Kochereshko acknowledges support from the “Electron Correlations in Systems with Strong Interaction” program of the Physical Sciences Division of the Russian Academy of Sciences. The work of A.V. Platonov was supported by program no. 9 “Terahertz Optoelectronics and Spintronics” of the Presidium of the Russian Academy of Sciences.
- 3.V. G. Dubrovskii, Theoretical Principles of Technology of Semiconductor Nanostructures (SPb. Gos. Univ., St. Petersburg, 2006) [in Russian].Google Scholar
- 5.M. J. Snelling, E. Blackwood, C. J. McDonagh, R. T. Harley, and C. T. B. Foxon, Phys. Rev. B 45, 3922(R) (1992).Google Scholar
- 7.L. D. Landau and E. M. Lifshitz, Course of Theoretical Physics, Vol. 3: Quantum Mechanics: Non-Relativistic Theory (Nauka, Moscow, 1974, 3th ed.; Pergamon, New York, 1977, 3rd ed.).Google Scholar
- 13.M. H. M. van Weert, N. Akopian, F. Kelkensberg, U. Perinetti, M. P. van Kouwen, J. Gόmez Rivas, M. T. Borgström, R. E. Algra, M. A. Verheijen, E. P. A. M. Bakkers, L. P. Kouwenhiven, and V. Zwiller, arXiv:0808.2908 [cond-mat.mes-hall].Google Scholar