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arXiv · 2111.05163

Quantization and coherent states for a time-dependent Landau problem

Latévi Mohamed Lawson
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Abstract

The ordinary Landau problem consists of describing a charged particle in time-independent magnetic field. In the present case the problem is generalized onto time-dependent uniform electric fields with time-dependent mass and harmonic frequency [1].The spectrum of a Hamiltonian describing this system is obtained. The configuration space wave functions of the model is expressed in terms of the generalised Laguerre polynomials. To diagonalize the time-dependent Hamiltonian we employ the Lewis-Riesenfeld method of invariants. To this end, we introduce an unitary transformation in the framework of the algebraic formalism to construct the invariant operator of the system and then to obtain the exact solution of the Hamiltonian. We recover the solutions of the ordinary Landau problem in the absence of the electric and harmonic fields, for a constant particle mass. The quantization of this system exhibits many symmetries such as $U(1), SU(2), SU(1,1)$. We therefore construct the coresponding coherent states and the associated photon added and nonlinear coherent states.

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Latévi Mohamed Lawson. 2021-11-09. Quantization and coherent states for a time-dependent Landau problem. https://arxiv.org/abs/2111.05163

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