Question
An electron moves in the potential well $P(x)=-\delta$ for $-a \leq x<0$ and $P(x)=\delta$ for $0<x \leq a$ (Fig. 13.7). Use first-order perturbation theory to compute the first four energy levels. Set up the expression for the first-order expansion coefficients for the lowest energy state.
Step 1
The Hamiltonian is given by \[H = -\frac{\hbar^2}{2m}\frac{d^2}{dx^2} + P(x)\] where $P(x)$ is the potential well, $\hbar$ is the reduced Planck's constant, $m$ is the mass of the electron, and $x$ is the position of the electron. Show more…
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