Introduction To Quantum Mechanics
3rd Edition
ISBN: 9781107189638
Author: Griffiths, David J., Schroeter, Darrell F.
Publisher: Cambridge University Press
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Chapter 9.3, Problem 9.11P
To determine
The analysis of scattering from a barrier with sloping walls by finding the tunneling probability.
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PROBLEM 2. Consider a spherical potential well of radius R and depth Uo,
so that the potential is U(r) = -Uo at r R.
Calculate the minimum value of Uc for which the well can trap a particle
with l = 0. This means that SE at Uo > Uc has at least one bound ground
state at l = 0 and E < 0. At Ug = Uc the bound state disappears.
A proton is confined in box whose width is d = 750 nm. It is in the n = 3 energy state. What is the probability that the proton will be found within a distance of d/n from one of the walls? Include a sketch of U(x) and ?(x).
Sketch the situation, defining all your variables
Problem # 2.
In the two-level system, estimate the emission line full width at half maximum (FWHM) for
spontaneous emission at 650 nm if the spontaneous radiative lifetime of the upper state is about
3,000 nanoseconds.
Chapter 9 Solutions
Introduction To Quantum Mechanics
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