Biest
Mar25-08, 09:24 PM
Hi,
So I am given linear combination state:
|\psi> = \cos \theta |0> + \sin \theta |1>
Now we are supposed to apply: x = \sqrt{\frac{\hbar}{2m\omega}} (\hat{A} + \hat{A^\dagger}) such that <\Psi|x|\Psi> so I can find the angle \theta maximizes the expected value.
I did that and got as far as
\sqrt{\frac{\hbar}{2m\omega}} (<\psi|\hat{A^\dagger}|\psi> + <\psi|\hat{A}|\psi>)
Substitute in for |\Psi>
\sqrt{\frac{\hbar}{2m\omega}} ( (<0|\cos \theta +<1| \sin \theta) \hat{A^\dagger} (\cos \theta |0> + \sin \theta |1>) + (<0|\cos \theta +<1| \sin \theta)\hat{A^\dagger} (\cos \theta |0> + \sin \theta |1>) )
Now I am getting confused as to how to apply the operator.
Thanks in advance.
Cheers,
Biest
EDIT:
I took an educated guess and got out \sqrt{\frac{\hbar}{2m\omega}} \sin 2\theta
So I am given linear combination state:
|\psi> = \cos \theta |0> + \sin \theta |1>
Now we are supposed to apply: x = \sqrt{\frac{\hbar}{2m\omega}} (\hat{A} + \hat{A^\dagger}) such that <\Psi|x|\Psi> so I can find the angle \theta maximizes the expected value.
I did that and got as far as
\sqrt{\frac{\hbar}{2m\omega}} (<\psi|\hat{A^\dagger}|\psi> + <\psi|\hat{A}|\psi>)
Substitute in for |\Psi>
\sqrt{\frac{\hbar}{2m\omega}} ( (<0|\cos \theta +<1| \sin \theta) \hat{A^\dagger} (\cos \theta |0> + \sin \theta |1>) + (<0|\cos \theta +<1| \sin \theta)\hat{A^\dagger} (\cos \theta |0> + \sin \theta |1>) )
Now I am getting confused as to how to apply the operator.
Thanks in advance.
Cheers,
Biest
EDIT:
I took an educated guess and got out \sqrt{\frac{\hbar}{2m\omega}} \sin 2\theta