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Dassinia
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Hello
I'm reaaaaaally stuck here, if someone can explain me it'd be great because i just dn't know how to do all that
Consider a system with the moment of inertia l=1
A base of the space of the states is constituted by the three eigenvectors of Lz |+1> , |0>, |-1> of eigenvalues +h, 0, -h (h=h/2π)
The Hamiltonian has the form : H=wo/h(Lu²-Lv²)
where Lu and Lv are the component of L in the directions Ou & Ov of the xOz plan, 45° from Ox and Oz. wo is a real constant.
a. Write the matrix representing H in the basis |+1> , |0> and |-1>
What are the stationnary states of the system and their energies ?
b. At t=0 the system is in the state
|ψ(0)>=1/√2(|+1>-|-1>)
What is |ψ(t)> at time t ? If we measure Lz what are the probabilities of the different results ?
c. Calculate <Lx>(t) <Ly>(t) & <Lz>(t)
a.I am soooo lost I know I have to find Lx and Lz first , then Lu & Lv to find H
But I just don't know how to do that
b. We have
|ψ(t)>=|ψ(0)>exp(-iHt/h)
|+1> and |-1> are not eigenstates of H so I have to express them in eigenstates of H but how ?
And I will have to convert the energies |En> found in term of |+1> AND |-1> , how ?
c.
Thanks
I'm reaaaaaally stuck here, if someone can explain me it'd be great because i just dn't know how to do all that
Homework Statement
Consider a system with the moment of inertia l=1
A base of the space of the states is constituted by the three eigenvectors of Lz |+1> , |0>, |-1> of eigenvalues +h, 0, -h (h=h/2π)
The Hamiltonian has the form : H=wo/h(Lu²-Lv²)
where Lu and Lv are the component of L in the directions Ou & Ov of the xOz plan, 45° from Ox and Oz. wo is a real constant.
a. Write the matrix representing H in the basis |+1> , |0> and |-1>
What are the stationnary states of the system and their energies ?
b. At t=0 the system is in the state
|ψ(0)>=1/√2(|+1>-|-1>)
What is |ψ(t)> at time t ? If we measure Lz what are the probabilities of the different results ?
c. Calculate <Lx>(t) <Ly>(t) & <Lz>(t)
Homework Equations
The Attempt at a Solution
a.I am soooo lost I know I have to find Lx and Lz first , then Lu & Lv to find H
But I just don't know how to do that
b. We have
|ψ(t)>=|ψ(0)>exp(-iHt/h)
|+1> and |-1> are not eigenstates of H so I have to express them in eigenstates of H but how ?
And I will have to convert the energies |En> found in term of |+1> AND |-1> , how ?
c.
Thanks