What Is the Correct Approach to Integrate the Wigner Function for Fock States?

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SUMMARY

The discussion focuses on integrating the Wigner Function for Fock states in quantum optics, specifically using the P-Glauber Sudarshan Function. The integral presented involves complex variables α and β, and the Dirac delta function δ(β). The user initially derived an expression involving exponential and factorial terms but was unable to match the expected result, which is expressed in terms of Laguerre polynomials and the error function. A suggestion was made to differentiate the Laguerre polynomial to potentially reformulate the integrand for further insights.

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Homework Statement


I am currently doing a problem in Quantum optics, specifically the problem of finding Wigner Function for Number states or Fock states. I am actually did the problem in a different way and found that Wigner function for Number states is proportional to product of error function and Laguerre polynomials, now I finding the Wigner function from P-Glauber Sudarshan Function, where I encountered this Integral,

$$ \frac{2 exp(|α|^2)} {π^3 n!}\ ∫ \frac{exp(-|β|^2-4|α||β|)}{π^2*n!}\ \frac{∂^(2n)}{∂β^n∂(β*)^n}\ δ^2(β) d^2β $$

δ(β) is dirac delta function and α,β are complex

The Attempt at a Solution


I tried the solve the integral but shifting the index and got
$$ \frac{2(-1)^n (4)^(2n) exp(-|α|^2) |α|^(2n)}{π^3 n!}\ $$
But the correct answer is in terms of product of Laguerre polynomial and error function. Please help
 
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While I don't know the answer here, I was thinking what if you reversed your thinking and tried differentiating the Laguerre polynomial and see if you can reformulate it into the integrand you have. It might give you insight on how to do the integral.
 

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