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DOE OSTI · 21428615

How to Solve Schroedinger Problems by Approximating the Potential Function

Ledoux, Veerle·Van Daele, Marnix
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Abstract

We give a survey over the efforts in the direction of solving the Schroedinger equation by using piecewise approximations of the potential function. Two types of approximating potentials have been considered in the literature, that is piecewise constant and piecewise linear functions. For polynomials of higher degree the approximating problem is not so easy to integrate analytically. This obstacle can be circumvented by using a perturbative approach to construct the solution of the approximating problem, leading to the so-called piecewise perturbation methods (PPM). We discuss the construction of a PPM in its most convenient form for applications and show that different PPM versions (CPM,LPM) are in fact equivalent.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSALGEBRAAPPROXIMATIONSCALCULATION METHODSDIFFERENTIAL EQUATIONSEQUATIONSFUNCTIONAL ANALYSISFUNCTIONSMATHEMATICAL SOLUTIONSMATHEMATICSMATRICESNUMERICAL ANALYSISPARTIAL DIFFERENTIAL EQUATIONSPERTURBATION THEORYPOLYNOMIALSPOTENTIALSSCHROEDINGER EQUATIONWAVE EQUATIONS

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Ledoux, Veerle, Van Daele, Marnix. 2010-09-30. How to Solve Schroedinger Problems by Approximating the Potential Function. https://doi.org/10.1063/1.3498561

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