Artificial intelligence has grown rapidly in recent years, with applications including speech recognition, image identification, medical diagnosis, and many others. Quantum technology, on the other hand, has been shown to be capable of computational power much beyond that of even the world’s most powerful supercomputer. Physicists at the University of Vienna have now created a novel technology known as a quantum memristor that might allow these two worlds to collide, unlocking previously unimaginable capabilities.
The experiment was carried out in partnership with the Italian National Research Council (CNR) and Politecnico di Milano on an integrated quantum processor that operates on single photons. The research was just published in the journal Nature Photonics.
Neural networks are mathematical models that are at the heart of all artificial intelligence applications. The biological structure of the human brain, which is made up of linked nodes, inspired these models.
Neural networks can be mathematically trained by tuning their internal structure until they are capable of human-level tasks, such as recognising our faces, interpreting medical images for the diagnosis, and even driving our cars, much like our brain learns by constantly rearranging the connections between neurons.
The development of the memristor in 2008 was one of the key game-changers in the area. The memory-resistor, or memristor, is a device that adjusts its resistance based on a memory of a previous current. Scientists noticed that the unique behaviour of memristors was remarkably comparable to that of brain synapses (among many other uses). As a result, the memristor has become a crucial component in neuromorphic designs.
Prof. Philip Walther and Dr Roberto Osellame of the University of Vienna, the National Research Council (CNR), and the Politecnico di Milano have now proved that it is possible to construct a device that has the same behaviour as a memristor.
The physicists overcame the difficulty by employing single photons, or single quantum particles of light, and using their unique capacity to propagate concurrently in a superposition of two or more routes. Single photons propagate via waveguides laser-written on a glass substrate and are steered on a superposition of many routes in their experiment.
“Unlocking the full potential of quantum resources within artificial intelligence is one of the greatest challenges of the current research in quantum physics and computer science”, says Michele Spagnolo, who is the first author of the publication in the journal “Nature Photonics”.
This remarkable discovery is a step closer to a world in which quantum artificial intelligence is a reality.