Once I have finished a deep work session of any length, I take a short break. However, I struggle to get back into that deep work state afterwards. Any tips for re-engaging with work after a break?

Go back to the beginning of when you first started your deep work session and remember why you started in the first place. Once you regain that moment, jump back in with the mindset that you want to finish. Breaks are a good thing in between sessions, over doing it can wear you out. Refocus and push on