This question already has an answer here:
I've been researching about helicopter flight without a tail rotor and the closest I've found is intermeshing rotors or this: https://www.quora.com/Why-dont-helicopters-have-rotor-blades-at-the-bottom
Looking at this new method:
Seen in this frame, the rotors are single winged and I'm guessing they rotate at opposite phases. What is this called and where can I find more information about it?