The integrated detector combines a photonic silicon chip with a microelectronic chip made of silicon and thus offers faster detection of quantum light. Photo credit: University of Bristol
Researchers have developed a tiny device that paves the way for more powerful quantum computers and quantum communication, making them significantly faster than the current state of the art.
Bristol-based researchers have developed a tiny device that paves the way for more powerful quantum computing and quantum communication, making them significantly faster than the current state of the art.
Researchers from the Bristol UniversityQuantum Engineering Technology Labs (QET Labs) and the Université Côte d’Azur have developed a new miniaturized light detector that can measure the quantum characteristics of light in more detail than ever before. The device, made up of two silicon chips working together, was used to measure the unique properties of “squeezed” quantum light at record speeds.
The use of unique properties of quantum physics promises new ways to surpass the current state of the art in the fields of computers, communication and measurement. Silicon photonics – where light is used as an information carrier in silicon microchips – is an exciting path to these next generation technologies.
“Squeezed light is a quantum effect that is very useful. It can be used in quantum communication and quantum computers and was already used by the LIGO and Virgo gravitational wave observatories to improve their sensitivity and to discover exotic astronomical events such as black hole Mergers. Improving measurement capabilities can therefore have a big impact, ”said Joel Tasker, co-lead author.
Measuring compressed light requires detectors designed for extremely low electronic noise in order to detect the weak quantum features of light. So far, however, such detectors have been limited in the speed of the measurable signals – around one billion cycles per second.
“This has a direct impact on the processing speed of new information technologies such as optical computers and communication with very little light. The higher the bandwidth of your detector, the faster you can perform calculations and transfer information, ”said co-lead author Jonathan Frazer.
The integrated detector has been clocked an order of magnitude faster than the previous state of the art, and the team is working on refining the technology so that it works even faster.
The footprint of the detector is less than a square millimeter – this small size enables the high speed performance of the detector. The detector consists of silicon microelectronics and a silicon photonics chip.
Researchers around the world have been studying how quantum photonics can be integrated on a chip to demonstrate scalable manufacturing.
“Much of the focus was on the quantum part, but now we’ve started integrating the interface between quantum photonics and electrical readout. This is necessary for the entire quantum architecture to work efficiently. For homodyne detection, the chip-scale approach results in a small footprint device for mass production and, most importantly, increased performance, ”said Professor Jonathan Matthews, who led the project.
Reference: “Silicon photonics with integrated electronics for 9 GHz measurement of squeezed light” by Tasker, J. et al., November 9, 2020, Nature photonics.
DOI: 10.1038 / s41566-020-00715-5
Support for this work includes Matthews’ European Research Council, starting with the ERC-2018-STG 803665 grant, “Photonics for Engineered Quantum Enhanced Measurement,” which aims at quantum-enhanced on-chip sensing capabilities, and the Engineering and Physical Sciences Research Council, which the scholarships from lead authors Joel Tasker and Jonathan Frazer. All funding sources are fully described in the paper.
The Quantum Engineering Technology Labs (QET Labs) at Bristol University were launched in April 2015 and include activities from over 100 academics, staff and students. It brings together the broader spectrum and related activities in Bristol to maximize the opportunities for new scientific discoveries that aid the development of engineering and technology.
The EPSRC-funded Quantum Engineering Center for Doctoral Training in Bristol provides an exceptional training and development experience for those pursuing careers in the emerging quantum technology industry or in academia. It supports the understanding of sound basic scientific principles and their practical application to real challenges.
