These kind of atom-like systems can be used as registers for a quantum computer. They allow you to store a qubit and apply gates to that qubit. It doesn’t make practical sense to use it to improve classical storage, although it actually can pack more information than a classical bit using “superdense coding” [0]
In case some is curious about how it is in Europe: I'm a PhD student (physics) in Denmark and I get 2500$/month after tax. I save from 1000$ to 1500$ each month. Disclaimer: I bike everywhere and share a 1400$/month flat with partner. Also, the entire pay comes directly from the university, I never had to apply to get funding after getting accepted (this was the main reason to go to Denmark).
[0] https://en.m.wikipedia.org/wiki/Superdense_coding