Transmission Coefficient of a double delta function potential

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The discussion focuses on calculating the reflection (R) and transmission (T) coefficients for a double delta function potential, specifically V(x) = |g| (δ(x+L) + δ(x-L)). There is confusion regarding whether to compute the T coefficients for each barrier separately and if they can be multiplied due to the negligible width of the delta functions. The wavefunction is defined for three regions, with the incident wave traveling from left to right, leading to the conclusion that F = 0. It is suggested that only one T coefficient is necessary for x > L, and the matching of wavefunctions should occur between the incident and reflected parts and the intermediate region. The discussion emphasizes the importance of proper wavefunction matching in calculating the total transmission.
jmm5872
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V(x) = |g| (δ(x+L)+δ(x-L)

Consider scattering from a repulsive twin-delta function potential.

Calculate R and T.

I'm mostly confused about computing the T coefficients for multiple barriers. Would I compute the T coefficient for the barrier at x = -L and at x = L seperately? Then, instead of having to take an integral for the total T, for a large forbidden region, I can simply multiply the two T coefficients together since the Δx is essentially zero for a delta well.

Also, for the wavefunction in each region I have:

ψI = Aeikx+Be-ikx for (x < -L)
ψII = Ceikx+De-ikx for (-L < x < L)
ψIII = Eeikx+Fe-ikx for (L < x )

But the incident wave is from left to right so F = 0. Am I on the right track?
 
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I think that you are on the right track.

Probably you only have one T; only for x > L, and then you don't actually match the I,R part to the T part, but rather match the I,R part to the left side of the intermediate part, and then match the right side of the intermediate part to the T part.
 
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