I would like to ask when we describe coherent light interacting with atoms, what's the difference in hot atom case and BEC regime?
In hot atom vapor, I know we could start with a simple interaction Hamiltonian with rotating wave approximation
and we usually neglect the atom kinetic part in the Hamiltonian, (or did we?). However, it seems to me that in BEC regime, we have to consider the recoil momentum effect.
1.Is there any substantial difference between the hot and BEC case?
2.Is there a similar interaction Hamiltonian in second quantization form in BEC regime?
Thanks in advance!