Computer Program Detail Page

Item Picture
Eigenstate Superposition Model
written by Wolfgang Christian
This applet illustrates the fundamental building blocks of one-dimensional quantum mechanics, the energy eigenfunctions¬† ψn(x) and energy eigenvalues En.  The user enters the expansion coefficients into a table and the simulation uses the superposition principle to construct and display a time-dependent wave function using either infinite square well (ISW) or simple harmonic oscillator (SHO) eigenfunctions.

Please note that this resource requires at least version 1.5 of Java (JRE).
1 source code document is available
Subjects Levels Resource Types
General Physics
- Computational Physics
Quantum Physics
- Bound State Systems
- General
- Upper Undergraduate
- Instructional Material
= Interactive Simulation
= Tutorial
Categories Intended Users Ratings
- Activity
- Learners
- Educators
  • Currently 0.0/5

Want to rate this material?
Login here!

Access Rights:
Free access
Additional information is available.
© 2008 Wolfgang Christian
infinite square well, quantum mechanics, simple harmonic oscillator, superposition principle
Record Creator:
Metadata instance created August 30, 2008 by Wolfgang Christian
Record Updated:
June 4, 2014 by Andreu Glasmann
Last Update
when Cataloged:
August 31, 2008
Other Collections:

Zeeman Effect

Author: MuckrakerW M
Posted: October 25, 2014 at 8:08AM

There are applets or even software that simulates the Zeeman Effect but I cannot find anything at all at this particular website which uses Ejs to create physics applets for use by scientists primarily illustrating Zeeman's effect. Anyone know why this is so?

» reply

Eigenstate Superposition Simulation

Author: MuckrakerW M
Posted: October 20, 2014 at 9:38PM

The ejs simulator certainly helps you to get a better understanding of how to compute the eigenfunctions and their corresponding eigenvalues. But this is done when you normalize the wave function, which, in order to be normalized must be square integrable and finite. Then you can observe depending on quantum number n the various energy eigenfunctions and values in the 1-d infinite square well as they oscillate at different wavelengths and amplitudes you can set again depending on your bounds, i.e. -a < x < a. Moreover that you do all this because the eigenfunctions are standing waves in a bound state and not traveling waves.

On the other hand, the harmonic oscillator is a bit different. That is, one must realize using such wave functions to solve the Schrodinger equation would not be so easy to do because of several problems that develop. One such being the quadratic x^2 and switching the constant -hbar/2m away from y'' in order to make it have a coefficient of one since it is the highest order derivative in the differential equation.

To make life a whole lot simpler we have to use the Hermite polynomials for the SHO which are not hard at all. For the most part if you know how to do power series in calculus then it is relatively easy to find solutions to the S.E. using Hermite polynomials and their recurrent relation from the Hermite differential equation.

» reply

Re: Eigenstate Superposition Simulation

Author: Bruce, ComPADRE Dir

Thank you for your comment. This is true, the Superposition Model uses the simple harmonic oscillator wavefunctions using the Hermite Polynomials, as outlined in the description.

» reply

Post a new comment on this item
ComPADRE is beta testing Citation Styles!

Record Link
AIP Format
W. Christian, Computer Program EIGENSTATE SUPERPOSITION MODEL (2008), WWW Document, (
W. Christian, Computer Program EIGENSTATE SUPERPOSITION MODEL (2008), <>.
APA Format
Christian, W. (2008). Eigenstate Superposition Model [Computer software]. Retrieved June 23, 2024, from
Chicago Format
Christian, Wolfgang. "Eigenstate Superposition Model." (accessed 23 June 2024).
MLA Format
Christian, Wolfgang. Eigenstate Superposition Model. Computer software. 2008. Java (JRE) 1.5. 23 June 2024 <>.
BibTeX Export Format
@misc{ Author = "Wolfgang Christian", Title = {Eigenstate Superposition Model}, Month = {August}, Year = {2008} }
Refer Export Format

%A Wolfgang Christian %T Eigenstate Superposition Model %D August 31, 2008 %U %O application/java

EndNote Export Format

%0 Computer Program %A Christian, Wolfgang %D August 31, 2008 %T Eigenstate Superposition Model %8 August 31, 2008 %U

Disclaimer: ComPADRE offers citation styles as a guide only. We cannot offer interpretations about citations as this is an automated procedure. Please refer to the style manuals in the Citation Source Information area for clarifications.

Citation Source Information

The AIP Style presented is based on information from the AIP Style Manual.

The APA Style presented is based on information from APA Electronic References.

The Chicago Style presented is based on information from Examples of Chicago-Style Documentation.

The MLA Style presented is based on information from the MLA FAQ.

This resource is stored in 3 shared folders.

You must login to access shared folders.

Save to my folders



Similar Materials