Schrödinger eq. with 3D spherical potential

maethros
Messages
8
Reaction score
0
Hello!

I'm trying to solve some old exam exercises to prepare for my qm exam next week.
Now I got a question I don't have any idea how to solve it. I hope somebody can help me:

"The radial Schrödinger equation in the case of a 3D spherical symmetric potential V(r) can be written in the form

-h^2/(2*m) * d^2u/dr^2 + [V(r) + (l*(l+1) / r^2)]*u = E*u

where u(r) = r*R(r). If V is attractive and vanishes exponentially at infinity, how does u(r) behave asymptotically for bound states?"



Thanks for helping!
 
Physics news on Phys.org
What can you say about the effective potential as r\rightarrow \infty? That should give you a pretty good idea of where to start. Also, I think this belongs in Homework Help.
 
as r-> inf, the potential goes to zero and the second term in the effective potential goes rapidly to zero (as there is a r^2)
 
Thread 'Need help understanding this figure on energy levels'
This figure is from "Introduction to Quantum Mechanics" by Griffiths (3rd edition). It is available to download. It is from page 142. I am hoping the usual people on this site will give me a hand understanding what is going on in the figure. After the equation (4.50) it says "It is customary to introduce the principal quantum number, ##n##, which simply orders the allowed energies, starting with 1 for the ground state. (see the figure)" I still don't understand the figure :( Here is...
Thread 'Understanding how to "tack on" the time wiggle factor'
The last problem I posted on QM made it into advanced homework help, that is why I am putting it here. I am sorry for any hassle imposed on the moderators by myself. Part (a) is quite easy. We get $$\sigma_1 = 2\lambda, \mathbf{v}_1 = \begin{pmatrix} 0 \\ 0 \\ 1 \end{pmatrix} \sigma_2 = \lambda, \mathbf{v}_2 = \begin{pmatrix} 1/\sqrt{2} \\ 1/\sqrt{2} \\ 0 \end{pmatrix} \sigma_3 = -\lambda, \mathbf{v}_3 = \begin{pmatrix} 1/\sqrt{2} \\ -1/\sqrt{2} \\ 0 \end{pmatrix} $$ There are two ways...
Back
Top