The Hamiltonian of a quantum rod with an ellipsoidal boundary is given after a coordinate transformation which changes the ellipsoidal boundary into a spherical one.We then study the first internal excited state energy,the excitation energy and the frequency of the transition spectral line between the first internal excited state and the ground state of the strong-coupling polaron in a quantum rod.The effects of the electron-phonon coupling strength,the aspect ratio of the ellipsoid,the transverse radius of quantum rods and the transverse and longitudinal effective confinement length are taken into consideration by using a linear combination operator and the unitary transformation methods.It is found that the first internal excited state energy,the excitation energy and the frequency of the transition spectral line are increasing functions of the electron-phonon coupling strength,whereas they are decreasing ones of the transverse radius of quantum rods and the aspect ratio.The first internal excited state energy,the excitation energy and the frequency of the transition spectral line increase with decreasing transverse and longitudinal effective confinement length.
This paper calculates the time evolution of the quantum mechanical state of an electron by using variational method of Pekar type on the condition of electric-LO-phonon strong coupling in a parabolic quantum dot. It obtains the eigenenergies of the ground state and the first-excited state, the eigenfunctions of the ground state and the first- excited state This system in a quantum dot may be employed as a two-level quantum system qubit. The superposition state electron density oscillates in the quantum dot with a period when the electron is in the superposition state of the ground and the first-excited state. It studies the influence of the electric field on the eigenenergies of the ground state, the first-excited state and the period of oscillation at the different electron-LO-phonon coupling constant and the different confinement length.
