Properties of excited state of the polaron in quantum rods

Abstract

Abstract:

Based on a coordinate transformation, we change the boundary potential of a quantum rods from the ellipsoidal form into an spherical one. And then the properties of the vibrational frequency, the first internal excited state energy, the excitation energy and the frequency of transition spectral line between the first internal excited state and the ground state of weak-coupling polaron in a quantum rod in a parabolic potential are studied by using the linear combination operator and the unitary transformation methods. Relations of the vibrational frequency, the first internal excited state energy, the excitation energy and the frequency of transition spectral line of polaron with the transverse and the longitudinal effective confinement length,the aspect ratio of the ellipsoid and the electron-phonon coupling strength were derived. Numerical calculation results show that the vibrational frequency, the first internal excited state energy, excitation energy and frequency of transition spectral line increase rapidly with decreasing transverse and longitudinal effective confinement length. The vibrational frequency and the first internal excited state energy are decreasing functions of the aspect ratio of the ellipsoid and the electron-phonon coupling strength,respectively. The excitation energy and frequency of transition spectral line are increasing functions of the aspect ratio when e’ >1, whereas it is decreasing function of one when e’<1. When e’=1, the excitation energy and frequency of transition spectral line have minimum values.

Key words: low dimensional structure, quantum rods, linear combination operator, polaron, excited state, aspect ratio

CLC Number:

O469

BAI Rui-feng, XIAO Jing-lin. Properties of excited state of the polaron in quantum rods[J]. J4, 2010, 27(6): 743-748.

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