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arXiv · 1809.03351

Bound states of Newton's equivalent finite square well

Amornthep Tita·Pichet Vanichchapongjaroen
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Abstract

In this paper, a 1-parameter family of Newton's equivalent Hamiltonians (NEH) for finite square well potential is analyzed in order to obtain bound state energy spectrum and wavefunctions. For a generic potential, each of the NEH is classically equivalent to one another and to the standard Hamiltonian yielding Newton's equations. Quantum mechanically, however, they are expected to be differed from each other. The Schrödinger's equation coming from each of NEH with finite square well potential is an infinite order differential equation. The matching conditions therefore demand the wavefunctions to be infinitely differentiable at the well boundaries. To handle this, we provide a way to consistently truncate these conditions. It turns out as expected that bound state energy spectrum and wavefunctions are dependent on the parameter $β,$ which is used to characterize different NEH. As $β\to 0,$ the energy spectrum coincides with that from the standard quantum finite square well.

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Amornthep Tita, Pichet Vanichchapongjaroen. 2018-09-10. Bound states of Newton's equivalent finite square well. https://doi.org/10.1142/s021773231850195x

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