Writing the wave function solutions for a particle in a 2-D box

Click For Summary
SUMMARY

The wave function solutions for a particle in a 2-D box are defined as $$\Psi_{n,m}(x,y,t) = \frac{2}{\sqrt{L_x L_y}} sin(\frac{n\pi}{L_x}x)sin(\frac{m\pi}{L_y}y)e^{-\frac{i\pi^2 \hbar^2 t}{2m}[\frac{n^2}{{L_x}^2}+\frac{m^2}{{L_y}^2}]}$$. The coefficients ##C_n## and ##C_m## represent the probability amplitudes, and the probability of the system being in a specific state is proportional to ##|C_{nm}|^2##, not ##|C_n C_m|^2##. This distinction is crucial for accurately describing the quantum state of the particle in the box.

PREREQUISITES
  • Understanding of quantum mechanics principles, specifically wave functions.
  • Familiarity with the mathematical representation of infinite square wells.
  • Knowledge of probability amplitudes and their significance in quantum mechanics.
  • Basic grasp of the Schrödinger equation and its applications in two-dimensional systems.
NEXT STEPS
  • Study the derivation of wave functions in quantum mechanics, focusing on infinite potential wells.
  • Learn about the implications of probability amplitudes in quantum state measurements.
  • Explore the mathematical techniques for solving the Schrödinger equation in multi-dimensional systems.
  • Investigate the role of boundary conditions in determining wave function solutions.
USEFUL FOR

Students and professionals in physics, particularly those specializing in quantum mechanics, as well as researchers working on quantum systems and wave function analysis.

Hamiltonian
Messages
296
Reaction score
193
The final wave function solutions for a particle trapped in an infinite square well is written as:

$$\Psi(x,t) = \Sigma_{n=1}^{\infty} C_n\sqrt{\frac{2}{L_x}}sin(\frac{n\pi}{L_x}x)e^{-\frac{in^2{\pi}^2\hbar t}{2m{L_x}^2}}$$

The square of the coefficient ##C_n## i.e. ##{|C_n|}^2## is proportional to the probability of the system being in that state on measurement.

The wave function solution of a particle in a 2-D box
$$\Psi_{n,m}(x,y,t) = \frac{2}{\sqrt{L_x L_y}} sin(\frac{n\pi}{L_x}x)sin(\frac{m\pi}{L_y}y)e^{-\frac{i\pi^2 \hbar^2 t}{2m}[\frac{n^2}{{L_x}^2}+\frac{m^2}{{L_y}^2}]}$$

is it correct to write the final solution as:
$$\Psi (x,y,t) = \Sigma_{n=1}^{\infty} \Sigma_{m=1}^{\infty}C_n C_m\frac{2}{\sqrt{L_x L_y}} sin(\frac{n\pi}{L_x}x)sin(\frac{m\pi}{L_y}y)e^{-\frac{i\pi^2 \hbar^2 t}{2m}[\frac{n^2}{{L_x}^2}+\frac{m^2}{{L_y}^2}]}$$

will the probability of the system being in a particular state be proportional to ##|C_n C_m|^2##?
 
Physics news on Phys.org
Not quite. Each combination of ##n, m## has its own coefficient: so, it should be ##C_{nm}##
 
  • Like
Likes   Reactions: Hamiltonian

Similar threads

  • · Replies 1 ·
Replies
1
Views
1K
  • · Replies 1 ·
Replies
1
Views
1K
  • · Replies 13 ·
Replies
13
Views
2K
  • · Replies 1 ·
Replies
1
Views
1K
  • · Replies 21 ·
Replies
21
Views
3K
  • · Replies 9 ·
Replies
9
Views
2K
  • · Replies 14 ·
Replies
14
Views
3K
  • · Replies 21 ·
Replies
21
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 29 ·
Replies
29
Views
5K