Not by name, specifically, but Slade Wilson volunteered to participate in a government experiment that was designed to allow him to access, like, 90% of his brain potential, as the idea is that humans only use a small percentage of what the supercomputer we call a brain can do. As a result, his physiology also was enhanced to lower superhuman levels, and he began operating as Deathstroke.

Also, the Project Atom that created Captain Atom, Major Force and Bombshell somewhat classifies.

It's called training

As was mentioned above, Deathstoke is the closest to a super soldier serum in DC, it's called the Enhanced Soldier Initiative

I would consider Miraclo (from Hourman) kind of a Supersoldier Serum that just lasts one hour. The Arrowverse used a Japanization of the name (Mirakuru) and was what they gave Slade Wilson.to become superhuman.

They wanted to use Venom on soldiers and used the prisoner Bane as a test subject.

Ah Deathstroke