. 24/7 Space News .
STELLAR CHEMISTRY
A quantum view of 'combs' of light
by Staff Writers
Stanford CA (SPX) Dec 17, 2021

The silicon carbide microrings developed by the Vuckovic Lab, as seen through a scanning electron microscope at the Stanford Nano Shared Facilities.

Unlike the jumble of frequencies produced by the light that surrounds us in daily life, each frequency of light in a specialized light source known as a "soliton" frequency comb oscillates in unison, generating solitary pulses with consistent timing.

Each "tooth" of the comb is a different color of light, spaced so precisely that this system is used to measure all manner of phenomena and characteristics. Miniaturized versions of these combs - called microcombs - that are currently in development have the potential to enhance countless technologies, including GPS systems, telecommunications, autonomous vehicles, greenhouse gas tracking, spacecraft autonomy and ultra-precise timekeeping.

The lab of Stanford University electrical engineer Jelena Vuckovic only recently joined the microcomb community. "Many groups have demonstrated on-chip frequency combs in a variety of materials, including recently in silicon carbide by our team. However, until now, the quantum optical properties of frequency combs have been elusive," said Vuckovic, the Jensen Huang Professor of Global Leadership in the School of Engineering and professor of electrical engineering at Stanford. "We wanted to leverage the quantum optics background of our group to study the quantum properties of the soliton microcomb."

While soliton microcombs have been made in other labs, the Stanford researchers are among the first to investigate the system's quantum optical properties, using a process that they outline in a paper published Dec. 16 in Nature Photonics. When created in pairs, microcomb solitons are thought to exhibit entanglement - a relationship between particles that allows them to influence each other even at incredible distances, which underpins our understanding of quantum physics and is the basis of all proposed quantum technologies. Most of the "classical" light we encounter on a daily basis does not exhibit entanglement.

"This is one of the first demonstrations that this miniaturized frequency comb can generate interesting quantum light - non-classical light - on a chip," said Kiyoul Yang, a research scientist in Vuckovic's Nanoscale and Quantum Photonics Lab and co-author of the paper. "That can open a new pathway toward broader explorations of quantum light using the frequency comb and photonic integrated circuits for large-scale experiments."

Proving the utility of their tool, the researchers also provided convincing evidence of quantum entanglement within the soliton microcomb, which has been theorized and assumed but has yet to be proven by any existing studies.

"I would really like to see solitons become useful for quantum computing because it's a highly studied system," said Melissa Guidry, a graduate student in the Nanoscale and Quantum Photonics Lab and co-author of the paper. "We have a lot of technology at this point for generating solitons on chips at low power, so it would be exciting to be able to take that and show that you have entanglement."

Between the teeth
Former Stanford physics professor Theodor W. Hansch won the Nobel Prize in 2005 for his work on developing the first frequency comb. To create what Hansch studied requires complicated, tabletop-sized equipment. Instead, these researchers chose to focus on the newer, "micro" version, where all of the parts of the system are integrated into a single device and designed to fit on a microchip. This design saves on cost, size and energy.

To create their miniature comb, the researchers pump laser light through a microscopic ring of silicon carbide (which was painstakingly designed and fabricated using the resources of the Stanford Nano Shared Facilities and Stanford Nanofabrication Facilities). Traveling around the ring, the laser builds up intensity and, if all goes well, a soliton is born.

"It's fascinating that, instead of having this fancy, complicated machine, you can just take a laser pump and a really tiny circle and produce the same sort of specialized light," said Daniil Lukin, a graduate student in the Nanoscale and Quantum Photonics Lab and co-author of the paper. He added that generating the microcomb on a chip enabled a wide spacing between the teeth, which was one step toward being able to look at the comb's finer details.

The next steps involved equipment capable of detecting single particles of the light and packing the micro-ring with several solitons, creating a soliton crystal. "With the soliton crystal, you can see there are actually smaller pulses of light in between the teeth, which is what we measure to infer the entanglement structure," explained Guidry. "If you park your detectors there, you can get a good look at the interesting quantum behavior without drowning it out with the coherent light that makes up the teeth."

Seeing as they were performing some of the first experimental studies of the quantum aspects of this system, the researchers decided to try to confirm a theoretical model, called the linearized model, which is commonly used as a shortcut to describe complex quantum systems. When they ran the comparison, they were astonished to find that the experiment matched the theory very well. So, while they have not yet directly measured that their microcomb has quantum entanglement, they have shown that its performance matches a theory that implies entanglement.

"The take-home message is that this opens the door for theorists to do more theory because now, with this system, it's possible to experimentally verify that work," said Lukin.

Proving and using quantum entanglement
Microcombs in data centers could boost the speed of data transfer; in satellites, they could provide more precise GPS or analyze the chemical composition of far-away objects. The Vuckovic team is particularly interested in the potential for solitons in certain types of quantum computing because solitons are predicted to be highly entangled as soon as they are generated.

With their platform, and the ability to study it from a quantum perspective, the Nanoscale and Quantum Photonics Lab researchers are keeping an open mind about what they could do next. Near the top of their list of ideas is the possibility of performing measurements on their system that definitively prove quantum entanglement.

Research Report: "Quantum optics of soliton microcombs"


Related Links
Stanford University
Stellar Chemistry, The Universe And All Within It


Thanks for being there;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceDaily Monthly Supporter
$5+ Billed Monthly


paypal only
SpaceDaily Contributor
$5 Billed Once


credit card or paypal


STELLAR CHEMISTRY
Discovery of split photon provides a new way to see light
Hanover NH (SPX) Dec 15, 2021
Nearly a century after Italian physicist Ettore Majorana laid the groundwork for the discovery that electrons could be divided into halves, researchers predict that split photons may also exist, according to a study from Dartmouth and SUNY Polytechnic Institute researchers. The finding that the building blocks of light can exist in a previously-unimaginable split form advances the fundamental understanding of light and how it behaves. The theoretical discovery of the split photon - known as ... read more

Comment using your Disqus, Facebook, Google or Twitter login.



Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle

STELLAR CHEMISTRY
Russia ready to 'fight' for space tourism supremacy

NASA selects second private astronaut mission to Space Station

Space Habitat Market size to grow by USD 94.92 Bn

Blue Origin plans to launch largest crew yet Saturday

STELLAR CHEMISTRY
SpaceX launches Turksat-5b

Webb placed on top of Ariane 5

ESA contract to advance Vega-C competitiveness

NASA 'Fires Up' Artemis RS-25 Rocket Engines with New Components

STELLAR CHEMISTRY
NASA's Ingenuity Mars Helicopter Reaches a Total of 30 Minutes Aloft

NASA's Perseverance Mars Rover Makes Surprising Discoveries

Out of the Shadows of the Maria Gordon notch: Sols 3328-3329

Cliffs and notches keeps Curiosity team busy: Sols 3330-3332

STELLAR CHEMISTRY
New technologies make Chinese astronauts' in-orbit lives easier

China's Long March carrier rocket embarks on 400th mission

On they march as China records 401st flight of Long March rocket family

First crew of space station provide a full update on China's progress

STELLAR CHEMISTRY
Investing recovery and resilience funds in space projects

New space economy ready to lift off thanks to Finnish innovation

Kepler Communications announces testing of Aether Network with Spire Global

Kleos' Patrol Mission Satellites Ready and Shipped to Launch Site

STELLAR CHEMISTRY
Long-Range Discrimination Radar Reshapes Adversaries' Calculus for Attacks Against US Homeland

Understanding cobalt's human cost

New smart-roof coating enables year-round energy savings

Nike buys virtual sneaker firm as metaverse buzz grows

STELLAR CHEMISTRY
Founding members of world's first independent space science mission confirmed

Life arose on hydrogen energy

Stellar "ashfall" could help distant planets grow

"Newer, nimbler, faster:" Venus probe will search for signs of life in clouds of sulfuric acid

STELLAR CHEMISTRY
NASA's Juno Spacecraft 'Hears' Jupiter's Moon

Deep Mantle Krypton Reveals Earth's Outer Solar System Ancestry

Cracking the mystery of nitrogen ice dynamics on Pluto

Planet decision that booted out Pluto is rooted in folklore, astrology









The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us.