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eigenpsi

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- Homework Statement
- I need to derive the equations 7.126 and 7.127(image posted) from Gerry/Knight's quantum optics book. The equations are the expectation values of the square of the quadrature operators for the even cat state.

- Relevant Equations
- <X1^2>=0.25 + ( (alpha)^2 )/(1+exp(-2alpha^2))

<X2^2>=0.25 - (exp(-2alpha^2)*(alpha)^2)/(1+exp(-2alpha^2))

I started and successfully showed that the expectation of X_1 and X_2 are zero. However the expectation value of X1^2 and X2^2 which I am getting is <X1^2> = 0.25 + \alpha^2 and <X2^2> = 0.25.

How do I derive the given equations?

How do I derive the given equations?

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