Finite Spherical Potential Well

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SUMMARY

The discussion centers on solving the finite spherical potential well defined by V(r) = 0 for r ≥ a and V(r) = -V0 for r < a. The user is attempting to determine the ground state energy and encounters the solution form involving c1 sin(kr) + c2 cos(kr) divided by r. The consensus is that the cosine term must be discarded due to its non-normalizable behavior at r=0, which leads to a divergence in the wave function. The user is confused about the implications of the Schrödinger equation and the behavior of the wave function at the origin.

PREREQUISITES
  • Understanding of quantum mechanics principles, specifically the Schrödinger equation.
  • Familiarity with spherical coordinates and their application in quantum systems.
  • Knowledge of boundary conditions and normalization of wave functions.
  • Concept of potential wells and energy states in quantum mechanics.
NEXT STEPS
  • Study the derivation of the Schrödinger equation in spherical coordinates.
  • Learn about the normalization conditions for wave functions in quantum mechanics.
  • Investigate the implications of singularities in quantum wave functions.
  • Explore the concept of bound states in potential wells and their energy levels.
USEFUL FOR

Students and professionals in quantum mechanics, particularly those studying potential wells, wave functions, and the mathematical foundations of quantum theory.

dsr39
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This is more a qualitative question than a specific homework question, but a homework problem got me wondering about it.

I was solving the finite potential well.

V(r) = 0 \hspace{1cm} r \geq a
V(r) = -V_0\hspace{1cm} r &lt; a

I am trying to solve for the ground state energy. When I find the forms of the solution in the interior of the well, I find that I get

\frac{c_1 \sin{(kr)} + c_2 \cos{(kr)}}{r}

I know from doing other reading that I should end up throwing away the cosine term, but I do not understand why.

I can see that it blows up at r=0, but it still looks like it will be normalizable to me since a volume integral in spherical coordinates provides an extra factor of r^2
 
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It doesn't satisfy the Schrödinger equation, because \nabla^2(1/r) \propto \delta^3(\vec x).
 
I don't understand that reply. I got it by solving the Schrödinger equation, so it must satisfy it, no?
 

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