New Quantum Computer Prototype Uses Photons In Hopes Of Increasing Speed, Power

By harnessing the unique world of quantum physics, scientists from the University of Vienna believe they have succeeded in prototyping an entirely new and efficient model of quantum computer: the boson sampling computer.

Because a quantum computer would work by manipulating quantum objects, including photons, electrons or atoms, scientists believe that it would be able to achieve far more far quicker than conventional computer models; however, despite a rapid development of quantum technology over the last several years, the development of such a machine has proven to be an elusive task, though some claim to have succeeded.

For this reason, the Austrian scientists, in collaboration with a team from the University of Jena, have set about using photons, a particular type of bosons, due to their high mobility.

Together, the researchers inserted photons into a complex optical network where they could propagate along many different paths.

“According to the laws of quantum physics, the photons seem to take all possible paths at the same time,” Phillip Walther of the Faculty of Physics explained in a press release regarding the discovery. “This is known as superposition. Amazingly, one can record the outcome of the computation rather trivially: one measures how many photons exit in which output of the network.

Because a classical computer relies on an exact description of the optical network in order to calculate the propagation of the photons through this circuit, it is ultimately unable to calculate a few dozen photons and an optical network with a hundred inputs and outputs.

The researchers, on the other hand, were able to meet the challenge and build a prototype based on theoretical proposal by the scientists at the Massachusetts Institute of Technology.

“It is crucial to verify the operation of a boson-sampling computer by comparing its outcome with the predictions of quantum physics,” first author of the study Max Tillmann said. “Fortunately, for small enough systems classical computers are able to accomplish this.”

For this reason, the researchers were able to successfully show that their realization of the boson-sampling computer not only works, but works with high precision, giving rise to the hope that the first out-performance of conventional computers may not be too far off yet.