A sizable collection of applet created by José Ignacio Fernández Palop.
amazing! the Ejs community is bigger than i thought

http://www.uco.es/hbarra José Ignacio Fernández Palop - Universidad de Córdoba [img]http://www.uco.es/hbarra/Blog/Elisabet.jpg[/img]

i use Google chrome which translate Spanish to English easily. the following is the translation of the page http://www.uco.es/hbarra/index.php/fc/appletsfc


The main physical phenomena that led to the establishment of quantum theory were the black-body thermal radiation, the photoelectric effect, Compton effect, etc.. In this section there are applications that intend to study each of these physical phenomena.
Thermal black-body radiation

The photoelectric effect
Photoelectric effect
Compton effect
The dispersion Thompson
Young's experiment
Diffraction through a slit


The Schrödinger equation of quantum mechanics is what Newton's equation of classical mechanics. In this section there are some applications that try to help understand the wave nature of particles analyzing various phenomena of the wave theory, such as: the phase velocity and group Fourier transform, etc. You can also see the solution of the Schrödinger equation of the simplest case, which is that of a free particle.
Dispersion of a particle system
Phase velocity and group
Fourier Integral type
Wave function in the representation of time
Fourier transform of a Gaussian wave packet
Temporal evolution of a free particle
Motion of a particle in a potential gradient


Dimensional potential are increasingly used to analyze the motion of particles in large application systems such as semiconductors. Today it has gotten even confine particles in one dimension but negligible dimension in the so-called quantum dots. In this section there are applications that allow the analysis of stationary and nonstationary solutions of several one-dimensional square potential.
Classical motion of a particle in square potential
Stationary solutions of the potential step
Motion of a wave packet in the potential step
Stationary solutions of the potential barrier
Motion of a wave packet in a potential barrier
Transmission coefficient of the potential barrier

Motion of a wave packet through cracks variables
Movement of a wave packet-through slits variable
Stationary states of the infinite well potential
Motion of a wave packet in an infinite well potential
Stationary states of finite potential well


The first applications of this section are devoted to analyzing how the solution of the Schrödinger equation for different time-independent one-dimensional potential. One of the most useful methods for solving one-dimensional square potential is the propagation matrix. By some applications can analyze the properties of this matrix. Finally, one of the most important potential is the harmonic oscillator because in many cases the motion of a system as it moves away slightly from equilibrium can be described by this potential. The latest applications to analyze the steady and unsteady solutions of the harmonic oscillator in quantum mechanics.
Solving the equation of time-independent Schrödinger
Solution of the Schrödinger equation for time-independent bound states
Propagation matrix
Propagation matrix for the energies of bound states of a finite well
Propagation matrix for a periodic potential
Bound states of simple harmonic oscillator
Motion of a wave packet in the harmonic oscillator potential
Classical limit of the harmonic oscillator file


The analysis of the classical limit and how quantum mechanics contains the classical as a limit case, yields approximate solutions of the Schrödinger equation time independent from the classical solution and this is the WKB approximation. By the following applications can analyze how the WKB approximate solution and how it can be used to calculate transmission coefficients and energies of bound states.
The principle of least action
Airy functions
Transmission coefficient for a triangular potential
WKB approximation to calculate the energies of bound states
The transmission coefficient using the WKB approximation
The WKB approximation when the energy is greater than the potential
Time evolution of a variable frequency oscillator


One of the most important mechanical quantities is the angular momentum as it has an associated conservation law. The following applications to analyze the eigenfunctions of angular momentum in quantum mechanics, which are harmonics eesféricos. The last application to analyze the fact that rotations do not commute among themselves.
Spherical harmonics
Court of spherical harmonics with the plane z


One of the few systems of interest to support an analytical solution in quantum mechanics is the hydrogen atom. The following applications to analyze the stationary states (orbitals) of the hydrogen atom, and the behavior of a hydrogen atom in a magnetic field and electric field.
Orbitals of the hydrogen atom
Orbitals of the hydrogen atom in three dimensions
Radial probability density of the first states of the hydrogen atom
The hydrogen atom in a magnetic field - Paramagnetism
The hydrogen atom in an electric field - Stark Effect


Spin is an intrinsic angular momentum with elementary particles. The following applications help We understand the properties of spin.
Rotations in spin space