How to measure the two-photon detuning in 3-level system?

[hongqiaozhang]

TL;DR Summary

how to measure the two-photon detuning in 3-level system

hi,everyone!
if i have a 3-level system,like this：

now,i want know how to measure the two-photon detuning in this system,and i‘ve known that,Δ2 and Δ3 are the two- and on-photon detunings,like this paper said:

my questions are below:
1.how other researchers measure these two parameters?
they measure the beat frequency of probing light and controling light? or they use an interferometer to measure the frequency of probing light?
2.can anyone give me some examples for these parameter,like What is the approximate magnitude of two-photon detuning，if you have any paper or publication about that,please let me know,i would be so grateful to receive your guidance!

Have a nice day,everyone!

 

[DrClaude]

I am theoretician, so I can't answer the first one. Maybe @f95toli or @Twigg can help.

For the second question, it will depend on the situation considered, but I would say that interesting physics will happen for anything from on resonance to a detuning of a few tens of $\Gamma$ (the line width of level $\ket{2}$).

 

[f95toli]

My guess is that the question is about optical transitions which is not my area of expertise.
Generally speaking, answers to "how do you measure" questions are really dependent on the details Clearly, the methods used will depend on the frequencies involved; for something like a 3-level system the underlying physics is not very different if you are working in the microwave regime (say SC qubits or Rydberg atoms) or in optics (or a mix of both, you can have 3-level systems with both optical and MW transitions) but experimentally it obviously makes a lot of difference...