I have never seen an aggressive rooster "calm down"....except once years ago. Shaun and I had one that, after about a year, started to run up to us and beat his wings in warning, then peck aggressively at our feet and legs. With his hands full of treats for the birds one day, Shaun was attacked by Old Red, so he kicked the offending rooster to save himself. The rooster tumbled, comb over tail, like a football for a couple of yards, then sulked for half a day. After that, he never bothered humans again and actually became a pretty awesome dude.
But that was an exception (and probably not a trustworthy taming method to use, either). I had another mean rooster this spring. Although he was quite a looker, none of the girls could stand him, and he created chaos in the flock. He'd chase them all over trying to mate, with squawking and feathers flying part of each ordeal. I had plans to get rid of him, but ended up not needing to. One night, the ladies rose up against Bad Leroy Brown. They pushed him off the roost and tried to make it look like an accident.
If your boy is new to the flock, the pecking order might need to be reestablished. This can be a stressful time. If he is not the only rooster, he may be picking fights with the little guys because he is sure to win. You may try separating the younger birds to get them away from the bully until they grow up. A bully hen, or one that is on the top of the pecking order, may also be able to put him in his place (stick them together for a few days and watch closely). If separation is not practical, I would encourage you to do whatever else is necessary to maintain order and peace for the rest of your birds because they deserve to not be harassed. Just like in human societies, those that assault others get sent "up the river."