A Rayleigh vs Raman scattering for low saturation

BillKet
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Hello! I have the following situation: I have a 3 level system, with 2 ground states, call them ##g_1## and ##g_2## and an excited state, ##e##, with energies ##E_{g1}<E_{g2}## and ##E_e##. I have a driving field with frequency ##\omega## such that ##\Gamma \ll \Delta \ll E_{g2}-E_{g1} \ll E_e - E_{g1}##, where ##\Gamma## is the linewidth of the excited state and ##\Delta## is the detuning of the excited state from the ##g_1\to e## transition. So basically the laser is very detuned from any transition in the system and we can assume that the laser power is small enough such that the saturation parameter, ##s## is much smaller than 1, so the probability of the atom getting excited to ##e## is virtually zero. I found in AMO books that in this case Rayleigh scattering dominates i.e. coherent scattering, compared to incoherent scattering i.e. decays from ##e## and the ratio of the 2 rates is ##\sim s##. However, as far as I can tell, these derivations don't take into account Raman transitions to ##g_2## (assuming we start in ##g_1##) in which ##e## doesn't get excited. These kinds of transitions are not Rayleigh (as the light frequency changes), but they are also not incoherent, as there is still a clear phase between the driving field and the emitted photon (but they have different frequencies). So, given my situation, how can I calculate the Rayleigh scattering rate vs Raman scattering rate (i.e. with both of them coherent processes and assuming that the dipole moment coupling between ##e## and ##g_1## is the same as the one between ##e## and ##g_2##)? Thank you!
 
Hi. I have got question as in title. How can idea of instantaneous dipole moment for atoms like, for example hydrogen be consistent with idea of orbitals? At my level of knowledge London dispersion forces are derived taking into account Bohr model of atom. But we know today that this model is not correct. If it would be correct I understand that at each time electron is at some point at radius at some angle and there is dipole moment at this time from nucleus to electron at orbit. But how...
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