A recently developed method for calculation of eigenvalues is applied to a four coupled oscillator system previously used to test more approximate methods. Analysis is presented to show how the present method scales for systems of two, three, and four coupled oscillator systems.
A program for the calculation of energy eigenvalues and eigenstates of a schrödinger equation
✍ Scribed by V. Fack; G. Vanden Berghe
- Publisher
- Elsevier Science
- Year
- 1986
- Tongue
- English
- Weight
- 724 KB
- Volume
- 39
- Category
- Article
- ISSN
- 0010-4655
No coin nor oath required. For personal study only.
✦ Synopsis
Title of the program: SCHROD dimensional Schrodinger equation Catalogue number: AADV dy(x) +(E-V(x))y(x)=0, Program obtainable from: CPC Program Library, Queen's Uni-where E denotes the eigenvalue parameter and V(x) the potenversity of Belfast, N. Ireland (see application form in this issue) tial. Computer: Siemens 7000 Series; Installation: CDR, Rijksuni-Method of solution versiteit Gent, Krijgslaan 281-S9, B 9000 Gent, Belgium A finite difference representation for d 2y(x)/dx2 is introduced such that the Schrodinger equation is transformed into Operating system: BS2000 an algebraic eigenvalue problem. This problem can be reduced to the calculation of the ei'genvalues and eigenvectors of a Programming language: FORTRAN 77 symmetric tridiagonal matrix, to which the NAG [11 routine FO2BEF can be applied. High speed storage required: 240 673 words Restrictions on the complexity of the problem No. of bits in a word: 32 It is assumed that the wavefunctions are restricted to obey the Dinchlet boundary condition y(x) = 0 at some x-value R. Peripherals used: card reader or VDU, printer Typical running time No. of lines in combined program and test deck: 439
The running time depends on the choice of the value R, on the number of terms in the finite difference representation for Keywords: SchrOdinger equation, energy eigenvalues and eigen-d2y(x)/dx2 and on the considered steplength h. functions, finite difference approach, reduction of band width Reference Nature of physical problem
[1] Numerical Algorithms Group (NAG) Library Manual, Calculation of the energy eigenvalues and eigenstates of the one Mark 8 (1981).
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