Understanding Squeezed States: Explanations & Evolution

[rudocurtir]

Hello. I'm posting here for the first time.

Can somebody give a short explanation on what the S states are?
How do we construct them? How do they take evolution in time?
I know that they are some sort of generalization of the coherent states, but do they come from the same Hamiltonian?

Hope you answer. Thanks.

PS: My name is Pablo, I study Physics at Santiago de Compostela (Spain).
http://

Sorry about my English

 

[dextercioby]

Would you mind if you were a bit more clear...?I mean,in what context did you meet these concepts...?What form does the Hamiltonian have...?

Daniel.

 

[vanesch]

Can somebody give a short explanation on what the S states are?
How do we construct them? How do they take evolution in time?
I

I'm no expert on this. What I vaguely know is the following: these are states that are solutions of the harmonic oscillator (usually in a quantum optics setting, where the harmonic oscillator is a mode of the EM field).
You know that coherent states are eigenstates of the annihilation operator, and they have particular properties (like the satisfy exactly the Heisenberg uncertainty relation: minimum uncertainty). Coherent states are in fact displacements of the vacuum state (if you apply the finite translation operator to the vacuum state, you obtain a coherent state).
But you can do more bricolage: you can also apply "squeeze" operators, which transform coherent states in other states (eh, squeezed states) ; these states also satisfy the HUP exactly.

If you want to have a very thorough reading on this, look at the chapter on coherent states, and the chapter on squeezed light (I think it is the last chapter) in Mandel and Wolf, the bible of quantum optics: "Optical coherence and quantum optics".

cheers,
Patrick.