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Close the 鈥渓oophole鈥 in Equation 9.78 by showing that ifl'=l=0thenn'l'm'|r|nlm=0

Short Answer

Expert verified

Showedthat Ifl'=l=0 then n'00|r|n00=0

Step by step solution

01

Given data:

No transitions occurs unless.l=1. . 9.78

l'=l=0

02

Showing that l'=l=0if then⟨n'l'm'|r|nlm⟩=0

The selection rules for states, with a spherically symmetric potential, the starting and ending states had to be related by:

[(l'+l+1)21][(l'l)21]=0

One solution of this equation leads to equation 9.78, which states that no transitions occurs unlessl=1.also the solutionl'=l=0seems to be correct and acceptable.

Then the two states where the transition occur between them aren'00|and|n00, the matrix elements of the transition rate formula have the form of:

b|r|a=n'00|r|n00

Forl=m=0 the angular part of the wave function is:

Y00=14

So the wave function is constant. In the above equation we have three integrals, and they depend on the values of x,yand zin spherical coordinates.

Forx=rsin()cos()we get:

n'00|x|n00~002sin2()cos()

Fory=rsin()sin(), we get:

n'00|y|n00~002sin2()sin()

And for,z=rcos() we get:

n'00|z|n00~002sin()cos()d

Thus:n'00|r|n00=0

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Most popular questions from this chapter

We have encountered stimulated emission, (stimulated) absorption, and spontaneous emission. How come there is no such thing as spontaneous absorption?

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H^'=U^(t);

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role="math" localid="1659004637631" a(t)={a0cos('t/2)+i'[a0(0)+b0]sin('t/2)}ei蝇t/2b(t)={b0cos('t/2)+i'[b0(0)+a0]sin('t/2)}ei蝇t/2

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'(0)2+2

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role="math" localid="1659004767993" P()=2(0)2+2,

as a function of the driving frequency (for fixed 0and ). Note that the maximum occurs at=0 Find the "full width at half maximum,"螖蝇

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