Nov 30, 2022
New quantum computing feat is a modern twist on a 150-year-old thought experiment
Posted by Kelvin Dafiaghor in categories: computing, quantum physics
A team of quantum engineers at UNSW Sydney has developed a method to reset a quantum computer—that is, to prepare a quantum bit in the ‘0’ state—with very high confidence, as needed for reliable quantum computations. The method is surprisingly simple: it is related to the old concept of ‘Maxwell’s demon’, an omniscient being that can separate a gas into hot and cold by watching the speed of the individual molecules.
“Here we used a much more modern ‘demon’—a fast digital voltmeter—to watch the temperature of an electron drawn at random from a warm pool of electrons. In doing so, we made it much colder than the pool it came from, and this corresponds to a high certainty of it being in the ‘0’ computational state,” says Professor Andrea Morello of UNSW, who led the team.