CHICAGO (Reuters) - U.S. scientists have found a way to levitate the very smallest objects using the strange forces of quantum mechanics, and said on Wednesday they might use it to help make tiny nanotechnology machines.

They said they had detected and measured a force that comes into play at the molecular level using certain combinations of molecules that repel one another.

The repulsion can be used to hold molecules aloft, in essence levitating them, creating virtually friction-free parts for tiny devices, the researchers said.

Federico Capasso, an applied physicist at Harvard University in Massachusetts, whose study appears in the journal Nature, said he believed that detection of this force opened the possibility of a whole new class of tiny gadgets.