Nanotechnology Now

Our NanoNews Digest Sponsors
Heifer International

Wikipedia Affiliate Button

Home > Press > 'Exceptional' research points way toward quantum discoveries: Rice University scientists make tunable light-matter couplings in nanotube films

Rice University scientists used nanotube films and polarized light to strongly couple light and matter progressively and on demand at room temperature. Their discovery of exceptional points in the resulting polaritons could allow researchers to explore novel quantum technologies like advanced information storage or one-dimensional lasers. (Credit: Weilu Gao/Rice University)
Rice University scientists used nanotube films and polarized light to strongly couple light and matter progressively and on demand at room temperature. Their discovery of exceptional points in the resulting polaritons could allow researchers to explore novel quantum technologies like advanced information storage or one-dimensional lasers. (Credit: Weilu Gao/Rice University)

Abstract:
Rice University scientists are known for exceptional research, but a new paper led by physicist Junichiro Kono makes that point most literally.

'Exceptional' research points way toward quantum discoveries: Rice University scientists make tunable light-matter couplings in nanotube films

Houston, TX | Posted on April 30th, 2018

The discovery of exceptional points in a unique material created by Kono’s lab is one of several revelations in a paper that appears in Nature Photonics.

These spectral singularities are central to another phenomenon, the team's newfound ability to continuously tune the transition between the weak and ultra-strong coupling of light and matter confined in a vacuum. That ability may give researchers the opportunity to explore novel quantum technologies like advanced information storage or one-dimensional lasers.

Kono and his colleagues have expertise in corralling photons and excitons (bound electron-hole pairs) in solids to form condensed matter in a quantum well. They reported on their ability to do so by manipulating electrons with light and a magnetic field in 2016.

In the same year, they announced their ability to make highly aligned, wafer-sized films of single-walled carbon nanotubes.

In the new work, Kono and Rice postdoctoral researcher and lead author Weilu Gao combined techniques from the earlier papers and used polarized light to trigger the formation of quasiparticles known as polaritons – strongly coupled light and matter – inside the one-dimensional nanotubes in a cavity at room temperature.

Because polaritons can only resonate along the aligned nanotubes' length, they appear when incoming light is polarized in the same direction. When turned 90 degrees, the polaritons disappear progressively.

The polarization angle at which polaritons appear and disappear is known as the exceptional point, and neither Kono nor Gao considered it important until a theorist friend stepped in.

"Discovering the point was important, and surprising," Kono said. "In our first version of the paper, we didn't really emphasize it. But while it was under review, we showed a theorist the data and he pointed out, 'You have this Dirac point-like feature here.' We started to look at it more carefully, and indeed there was an exceptional point."

Dirac points are a characteristic of graphene; they appear where the material's conduction and valence bands connect to make it a perfect conductor of electricity. In semiconductor materials, the energetic separation between bands determines the material's band gap.

Exceptional points have been studied in other contexts; in recent experiments, scientists showed light itself could be slowed or stopped at just such a point.

"A lot of the anomalous properties of electrons in graphene are related to the existence of this special point, called the Dirac point, or energy-zero point," Kono said. "Graphene's band structure is completely untraditional compared with solid semiconductors like gallium arsenide or silicon, which have conduction and valence bands that define their band gap.

"In our case, we have a kind of band gap between the upper and lower polaritons when polarized light is parallel to the films, but turning the light polarization changes everything. When you hit the exceptional point, the band gap closes and polaritons disappear."

Kono said the work also demonstrates that the aligned nanotubes cooperate with each other. "The vacuum Rabi splitting (a measure of coupling strength between photons in the vacuum and electrons in the solid film) increases as we increase the number of nanotubes," he said. "This is evidence that the nanotubes coherently cooperate as they interact with the cavity photons."

Gao said the Rice experiment suggested a way might be found to create photons – elemental particles of light – from a vacuum. That could be important for quantum-level storage as a way to extract data from qubits.

"There are theoretical proposals for converting virtual photons into real photons, sometimes called Casimir photons," Kono said. "We could have matter inside a cavity interacting with the vacuum, and when we trigger the system somehow we destroy the coupling, and suddenly photons come out. That's an experiment we want to do, because producing photons on demand from a vacuum would be cool."

Co-authors of the paper are Rice graduate student Xinwei Li and Motoaki Bamba, an associate professor at Osaka University. Kono is a professor of electrical and computer engineering, of physics and astronomy, and of materials science and nanoengineering.

The Department of Energy Basic Energy Science Office, the National Science Foundation, the Robert A. Welch Foundation, the PRESTO program of the Japan Science and Technology Agency and the ImPACT program of the Government of Japan’s Council for Science, Technology and Innovation supported the research.

####

About Rice University
Located on a 300-acre forested campus in Houston, Rice University is consistently ranked among the nation’s top 20 universities by U.S. News & World Report. Rice has highly respected schools of Architecture, Business, Continuing Studies, Engineering, Humanities, Music, Natural Sciences and Social Sciences and is home to the Baker Institute for Public Policy. With 3,970 undergraduates and 2,934 graduate students, Rice’s undergraduate student-to-faculty ratio is just under 6-to-1. Its residential college system builds close-knit communities and lifelong friendships, just one reason why Rice is ranked No. 1 for quality of life and for lots of race/class interaction and No. 2 for happiest students by the Princeton Review. Rice is also rated as a best value among private universities by Kiplinger’s Personal Finance. To read “What they’re saying about Rice,” go to http://tinyurl.com/RiceUniversityoverview .

Follow Rice News and Media Relations via Twitter @RiceUNews

For more information, please click here

Contacts:
David Ruth
713-348-6327


Mike Williams
713-348-6728

Copyright © Rice University

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related Links

Read the abstract at:

Kono Laboratory:

Motoaki Bamba:

Rice Department of Electrical and Computer Engineering:

Rice Department of Physics and Astronomy:

Rice Department of Materials Science and NanoEngineering:

Related News Press

Graphene/ Graphite

Drilling speed increased by 20% – yet another upgrade in the oil & gas sector made possible by graphene nanotubes January 15th, 2019

Boffins manage to keep graphene qubits 'quantum coherent' for all of 55... nanoseconds: Doesn't sound very long, but it could have big implications for quantum computing January 3rd, 2019

Holey graphene as Holy Grail alternative to silicon chips December 28th, 2018

News and information

Drilling speed increased by 20% – yet another upgrade in the oil & gas sector made possible by graphene nanotubes January 15th, 2019

Chirality in 'real-time' January 14th, 2019

New materials could help improve the performance of perovskite solar cells January 11th, 2019

Media invited to open meeting on the future of quantum technology held at RIT Jan. 23-25: Leaders from NASA, NSF, NIST and Sandia National Laboratory to attend January 11th, 2019

Quantum Physics

Quantum chemistry on quantum computers: A quantum algorithm for tracking complex chemical reactions with neither performing demanding post-Hartree-Fock calculations nor exponential time explosion January 4th, 2019

Satellite study proves global quantum communication will be possible December 28th, 2018

Govt.-Legislation/Regulation/Funding/Policy

2D materials may enable electric vehicles to get 500 miles on a single charge January 11th, 2019

Spintronics 'miracle material' put to the test: Physicists build devices using mineral perovskite January 11th, 2019

Cartilage could be key to safe 'structural batteries' January 11th, 2019

Arrowhead Pharmaceuticals Files for Regulatory Clearance to Begin Phase 1 Study of ARO-APOC3 for Treatment of Hypertriglyceridemia January 7th, 2019

Possible Futures

Chirality in 'real-time' January 14th, 2019

Media invited to open meeting on the future of quantum technology held at RIT Jan. 23-25: Leaders from NASA, NSF, NIST and Sandia National Laboratory to attend January 11th, 2019

Spintronics 'miracle material' put to the test: Physicists build devices using mineral perovskite January 11th, 2019

Cartilage could be key to safe 'structural batteries' January 11th, 2019

Chip Technology

Spintronics 'miracle material' put to the test: Physicists build devices using mineral perovskite January 11th, 2019

Nanometrics to Participate in the 21st Annual Needham Growth Conference January 7th, 2019

Holey graphene as Holy Grail alternative to silicon chips December 28th, 2018

Study on low noise, high-performance transistors may bring innovations in electronics December 28th, 2018

Nanotubes/Buckyballs/Fullerenes/Nanorods

Drilling speed increased by 20% – yet another upgrade in the oil & gas sector made possible by graphene nanotubes January 15th, 2019

Chemical synthesis of nanotubes: Nanometer-sized tubes made from simple benzene molecules January 11th, 2019

'Smart skin' simplifies spotting strain in structures: Rice U. invention can use fluorescing carbon nanotubes to reveal stress in aircraft, structures November 15th, 2018

Ultrasensitive toxic gas detector October 31st, 2018

Optical computing/Photonic computing

Media invited to open meeting on the future of quantum technology held at RIT Jan. 23-25: Leaders from NASA, NSF, NIST and Sandia National Laboratory to attend January 11th, 2019

An important step towards completely secure quantum communication networks November 30th, 2018

Bending light around tight corners without backscattering losses: New photonic crystal waveguide based on topological insulators paves the way to build futuristic light-based computers November 19th, 2018

GaN Rising: UC Santa Barbara electrical and computer engineering professor Umesh Mishra to deliver 63rd Annual Faculty Research Lecture November 16th, 2018

Discoveries

Chirality in 'real-time' January 14th, 2019

New materials could help improve the performance of perovskite solar cells January 11th, 2019

Spintronics 'miracle material' put to the test: Physicists build devices using mineral perovskite January 11th, 2019

Cartilage could be key to safe 'structural batteries' January 11th, 2019

Materials/Metamaterials

Drilling speed increased by 20% – yet another upgrade in the oil & gas sector made possible by graphene nanotubes January 15th, 2019

2D materials may enable electric vehicles to get 500 miles on a single charge January 11th, 2019

New materials could help improve the performance of perovskite solar cells January 11th, 2019

Spintronics 'miracle material' put to the test: Physicists build devices using mineral perovskite January 11th, 2019

Announcements

Drilling speed increased by 20% – yet another upgrade in the oil & gas sector made possible by graphene nanotubes January 15th, 2019

Chirality in 'real-time' January 14th, 2019

Spintronics 'miracle material' put to the test: Physicists build devices using mineral perovskite January 11th, 2019

Cartilage could be key to safe 'structural batteries' January 11th, 2019

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals/White papers

2D materials may enable electric vehicles to get 500 miles on a single charge January 11th, 2019

New materials could help improve the performance of perovskite solar cells January 11th, 2019

Spintronics 'miracle material' put to the test: Physicists build devices using mineral perovskite January 11th, 2019

Cartilage could be key to safe 'structural batteries' January 11th, 2019

Grants/Sponsored Research/Awards/Scholarships/Gifts/Contests/Honors/Records

Scientists program proteins to pair exactly: Technique paves the way for the creation of protein nanomachines and for the engineering of new cell functions December 21st, 2018

Strem Chemicals, Inc., Receives National Performance Improvement Honor: Company Recognized for Stakeholder Communications December 20th, 2018

Superfluidity: what is it and why does it matter? December 20th, 2018

Arrowhead Pharmaceuticals Reports Inducement Grants under NASDAQ Marketplace Rule 5635(c)(4) December 18th, 2018

Photonics/Optics/Lasers

Media invited to open meeting on the future of quantum technology held at RIT Jan. 23-25: Leaders from NASA, NSF, NIST and Sandia National Laboratory to attend January 11th, 2019

Carrying and releasing nanoscale cargo with 'nanowrappers': Nanocubes with hollow interiors and surface openings whose shape, size, and location are precisely controlled could be used to load and unload materials for biomedical, catalysis, and optical sensing applications January 3rd, 2019

Nanoscribe Presents Successor Model Photonic Professional GT2 for High-Resolution 3D Microfabrication: The first ever production of structures in millimeter size with micrometer precision December 4th, 2018

CEA-Leti Extends 300mm Line and Adds Avenues for Developing Disruptive Technologies: Execution Relies on CEA-Leti’s Fully Implemented Technology With Module-Level Innovations & Devices and Their Architectures December 3rd, 2018

Research partnerships

Chirality in 'real-time' January 14th, 2019

Ultra-sensitive sensor with gold nanoparticle array January 9th, 2019

DNA design that anyone can do: Computer program can translate a free-form 2-D drawing into a DNA structure January 4th, 2019

Revealing hidden spin: Unlocking new paths toward high-temperature superconductors: Berkeley Lab researchers uncover insights into superconductivity, leading potentially to more efficient power transmission January 4th, 2019

Quantum nanoscience

Spintronics 'miracle material' put to the test: Physicists build devices using mineral perovskite January 11th, 2019

Quantum chemistry on quantum computers: A quantum algorithm for tracking complex chemical reactions with neither performing demanding post-Hartree-Fock calculations nor exponential time explosion January 4th, 2019

Boffins manage to keep graphene qubits 'quantum coherent' for all of 55... nanoseconds: Doesn't sound very long, but it could have big implications for quantum computing January 3rd, 2019

Researchers make liquid crystals do the twist: UMD engineers and scientists measure previously unexamined tiny force December 21st, 2018

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project