With the development of a scalable quantum computing platform on a photonic chip the size of a penny, researchers have been able to drastically reduce the size and number of devices needed to achieve quantum speed. This could accelerate the transition from bulk optics to integrated photonics and bring quantum computing into real-world conditions.
Led by Xu Yi, an assistant professor of electrical and computer engineering at the University of Virginia (UVA) School of Engineering and Applied Science (Charlottesville, VA), the research team’s photonics-based method works because a field of light is full spectrum, and “each light wave in the spectrum has the potential to become a quantum unit.” According to the researchers, by entangling fields of light, the light could achieve a quantum state.
Quantum computers—unlike desktop and laptop computers, which process information in a string of bits—process information in parallel, meaning “they don’t have to wait for one sequence of information to be processed before they can compute more.” Gumode (quantum mode) spans the full spectrum of variables between one and zero, the researchers note.
In their study, they created a quantum source in an optical microresonator, “a ring-shaped, millimeter-sized structure that envelopes the photons and generates a microcomb” and device that efficiently converts photons from single to multiple wavelengths. Light circulates around the ring to build up optical power; the researchers note this increases the chance for photons to interact, which produces quantum entanglement between fields of light in the microcomb.
With multiplexing, 40 qumodes from a single microresonator on a chip were generated, “proving that multiplexing of quantum modes can work in integrated photonic platforms.” The team estimates that they could potentially generate thousands of qumodes from a single device.
“The future of the field is integrated quantum optics,” says researcher Olivier Pfister, a professor of quantum optics and quantum information at UVA. “Only by transferring quantum optics experiments from protected optics labs to field-compatible photonic chips will bona fide quantum technology be able to see the light of day.” Reference: Z. Yang et al., Nat. Commun., 12, 4781 (2021); doi.org/10.1038/s41467-021-25054-z.
Justine Murphy | Multimedia Director, Digital Infrastructure
Justine Murphy is the multimedia director for Endeavor Business Media's Digital Infrastructure Group. She is a multiple award-winning writer and editor with more 20 years of experience in newspaper publishing as well as public relations, marketing, and communications. For nearly 10 years, she has covered all facets of the optics and photonics industry as an editor, writer, web news anchor, and podcast host for an internationally reaching magazine publishing company. Her work has earned accolades from the New England Press Association as well as the SIIA/Jesse H. Neal Awards. She received a B.A. from the Massachusetts College of Liberal Arts.