It appears to be Albizia julibrissin, mimosa tree. Some people like it. Some people consider it a weed. It reseeds generously. It is fairly invasive in the SE US.

I also thought silk tree.

Albizia. shudder.

Weak, fast-growing trees. The last hurricane downed so many albizias (and they destroyed power lines) that electricity was out for 3 weeks.

However, they smell like peonies when they are in bloom.

Really? I have no idea what peonies smell like, but sometimes there's a heavy, not-quite-pleasant fragrance of something in bloom. I wonder if that's the albizia.