On the position dependent effective mass Hamiltonian

Kalpana Biswas; Jyoti Prasad Saha; Pinaki Patra

doi:10.1140/epjp/s13360-020-00476-8

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arXiv · 1910.09287

On the position dependent effective mass Hamiltonian

Kalpana Biswas·Jyoti Prasad Saha·Pinaki Patra

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Abstract

Noncommutivity of position and momentum makes it difficult to formulate the unambiguous structure of the kinetic part of Hamiltonian for the position-dependent effective mass (PDEM). Various existing proposals of writing the viable kinetic part of the Hamiltonian for PDEM, conceptually lack from first principle calculation. Starting from the first principle calculation, in this article, we have advocated the proper self-adjoint form of the kinetic part of Hamiltonian for PDEM. We have proposed that ambiguity of construction of viable kinetic part for PDEM can be avoided if one takes the care from the Classical level combination of position and momentum. \\ In the quantum level, the spatial points do not appear in equivalent footing for the measure of inertia (mass). This exhibits the existence of an inertia potential. Thus the new structure of the Kinetic part differs from the existing structure of the kinetic part of Hamiltonian by providing an extra potential like contribution. This inertia potential can be absorbed with the external potential and redefine the known structure of PDEM under this effective potential. This enables us to apply the existing formalism of quantum mechanics. The coherent state structures for the newly proposed form of Hamiltonian are provided for a few simple experimentally important models.

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Kalpana Biswas, Jyoti Prasad Saha, Pinaki Patra. 2019-09-30. On the position dependent effective mass Hamiltonian. https://doi.org/10.1140/epjp/s13360-020-00476-8

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