Jerry Robinson was getting some notoriety within the comic book ranks as one of the ghosts for Bob Kane on the hit Batman series first under Kane himself and later for DC directly. Then he was given the chance to create his own character for the up and coming comic book company Spark Publications, a character who spoke to a new age defined by a new weapon. He co-created with writer Ken Crossen what is almost certainly the first Atomic Age superhero when Atoman debuted in 1946.
But Spark was a small company and didn't last, and neither did Atoman having but two issues published.
Here is a link to read the debut issue.