Undergrad Two-photon Stimulated Raman Transitions

[Nijiro]

Hello everyone!

I don't know much about quantum physics. I'm an amator, but I want to expand and deepen my knowledge in quantum. So, I decided on the Quantum Gravity Gradiometer to be the subject of my supervised personal initiative work. But I'm currently stuck with many things among which are Raman Transitions. So, the gradiometer uses atom interferometry, which is realized through two-photon stimulated Raman Transitions. I read the letter published by Mark Kasevich and Steven Chu on the matter, I got the gist of it: it's similar to a Mach Zenhder interferometer with the light and atoms roles interchanged. The interferometer uses Raman pulses and I assume that they're Laser beams with specific frequencies to stimulate Raman Transitions in atoms (please correct me if I'm mistaken). However, I still don't get what are the "two photons" in "Two-photon Stimulated Raman Transition"? Wikipedia says that the molecule simultaneously absorbs both pump and Stokes photons. I assume they are the "two photons". But what is a Stokes photon? All I get when I google it are Stokes lines and Stokes shift.

Please ask me for clarification if any of my sentences is ambiguous as I'm not native in English.
Thank you all in advance.

 

[PeterDonis]

Do you have any references for any of the terms that you put in bold in your post?

 

[Nijiro]

Do you have any references for any of the terms that you put in bold in your post?

Hello!
Yes, I do.
- Mark Kasevich and Steven Chu, Atomic interferometry using stimulated Raman transitions, Phys. Rev. Lett. 67, 181 – Published 8 July 1991.
DOI: https://doi.org/10.1103/PhysRevLett.67.181
- Ben Stray, A Cold Atom Gravity Gradiometer with Field Application Performance. Thesis, Univ. Birmingham (2021), pp 21-43.
https://etheses.bham.ac.uk/id/eprint/11762/1/Stray2021PhD.pdf