This sentence is an example of subject-auxiliary inversion (often shortened to just inversion.)
In inversion, we reverse the usual order and place the verb before the subject. We often use inversion to emphasize an action (as you suggest.)
We use inversion in common speech when we ask questions, and after neither, nor, and so:
- Does she like it?
- Neither/nor does he.
- So do they.
In more formal speech and in writing, inversion is used in many other instances in English; it is treated in every grammar book. The Cambridge Dictionaries site explains it here. The specific adverb phrase "only after" is presented here.
You will find many similar questions here tagged with subj-aux-inversion.