Nanotechnology Now

Our NanoNews Digest Sponsors
Heifer International



Home > Press > Chaotic electrons heed ‘limit’ in strange metals

Abstract:
Electrons in metals try to behave like obedient motorists, but they end up more like bumper cars. They may be reckless drivers, but a new Cornell-led study confirms this chaos has a limit established by the laws of quantum mechanics.

Chaotic electrons heed ‘limit’ in strange metals

Ithaca, NY | Posted on July 30th, 2021

The team’s paper, “Linear-in Temperature Resistivity From an Isotropic Planckian Scattering Rate,” written in collaboration with researchers led by Louis Taillefer from the University of Sherbrooke in Canada, published July 28 in Nature. The paper’s lead author is Gael Grissonnanche, a postdoctoral fellow with the Kavli Institute at Cornell for Nanoscale Science.

Metals carry electric current when electrons all move together in tandem. In most metals, such as the copper and gold used for electrical wiring, the electrons try to avoid each other and flow in unison. However, in the case of certain “strange” metals, this harmony is broken and electrons dissipate energy by bouncing off each other at the fastest rate possible. The laws of quantum mechanics essentially play the role of an electron traffic cop, dictating an upper limit on how often these collisions can occur. Scientists previously observed this limit on the collision rate, also known as the “Planckian limit,” but there is no concrete theory that explains why the limit should exist, nor was it known how electrons reach this limit in strange metals. So the researchers set out to carefully measure it.

“Empirically, we’ve known that electrons can only bounce into each other so fast. But we have no idea why,” said Brad Ramshaw, the Dick & Dale Reis Johnson Assistant Professor in the College of Arts and Sciences, and the paper’s senior author. “Before, the ‘Planckian limit’ was just kind of inferred from data using very simple models. We did a very careful measurement and calculation and showed that it really is obeyed right down to the fine details. And we found that it’s isotropic, so it’s the same for electrons traveling in any direction. And that was a big surprise.”

The researchers focused their study on a copper oxide-based high-temperature superconductor known as a cuprate. Working with collaborators at the National High Magnetic Field Laboratory in Tallahassee, Florida, they introduced a sample of cuprate metal into a 45-tesla hybrid magnet – which holds the world record for creating the highest continuous magnetic field – and recorded the change in the sample’s electrical resistance while shifting the magnetic field’s angle. Ramshaw’s team then spent the better part of two years creating numerical data analysis software to extract the pertinent information.

Surprisingly, they were able to analyze their data with the same relatively simple equations used for conventional metals, and they found the cuprate metal’s electrons obeyed the Planckian limit.

“This approach that we used was supposed to be too naïve,” Grissonnanche said. “For scientists in the field, it is not obvious a priori that this should work, but it does. So with this new discovery, we have killed two birds with one stone: we have extended the validity of this simple approach to strange metals and we have accurately measured the Planckian limit. We are finally unlocking the enigma behind the intense motions of electrons in strange metals.”

“It doesn’t seem to depend on the details of the material in particular,” Taillefer said. “So it has to be something that’s almost like an overriding principle, insensitive to detail.”

Ramshaw believes that other researchers may now use this calculation framework to analyze a wide class of experimental problems and phenomena. After all, if it works in strange metals, it should work in many other areas.

And perhaps those strange metals are a little more orderly than previously thought.

“You’ve got these wildly complicated microscopic ingredients and quantum mechanics and then, out the other side, you get a very simple law, which is the scattering rate depends only on the temperature and nothing else, with a slope that’s equal to the fundamental constants of nature that we know,” he said. “And that emergence of something simple from such complicated ingredients is really beautiful and compelling.”

Such discoveries may also enable deeper understanding of the connections between quantum systems and similar phenonmena in gravitation, such as the physics of black holes – in effect, bridging the dizzyingly small world of quantum mechanics and their “dual” theories in general relativity, two branches of physics that scientists have been trying to reconcile for nearly a century.

###

Co-authors include doctoral student Yawen Fang and researchers from Université de Sherbrooke in Canada, University of Texas at Austin, the National High Magnetic Field Laboratory and University of Warwick in the United Kingdom.

The research was supported in part by the National Science Foundation, the European Research Council, the Canadian Institute for Advanced Research, the Natural Sciences and Engineering Research Council of Canada, the Canada First Research Excellence Fund and the Gordon and Betty Moore Foundation's EPiQS Initiative.

####

For more information, please click here

Contacts:
Becka Bowyer

Office: 607-220-4185

Copyright © Cornell 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

Paper:

Related News Press

News and information

Drawing data in nanometer scale September 30th, 2022

Researchers unveil mystery inside Li- o2 batteries September 30th, 2022

Synthesis of air-stable room-temperature van der Waals magnetic thin flakes September 30th, 2022

ACM Research Launches New Furnace Tool for Thermal Atomic Layer Deposition to Support Advanced Semiconductor Manufacturing Requirements: Ultra Fn A Furnace Tool Shipped to China-Based Foundry Customer September 30th, 2022

Quantum Physics

Key element for a scalable quantum computer: Physicists from Forschungszentrum Jülich and RWTH Aachen University demonstrate electron transport on a quantum chip September 23rd, 2022

Lattice distortion of perovskite quantum dots induces coherent quantum beating September 9th, 2022

Bound by light: Glass nanoparticles show unexpected coupling when levitated with laser light August 26th, 2022

Master equation to boost quantum technologies: FQXi-funded analysis will help physicists exert exquisitely precise real-time feedback control over quantum systems August 26th, 2022

Quantum chemistry

Scientists capture a ‘quantum tug’ between neighboring water molecules: Ultrafast electrons shed light on the web of hydrogen bonds that gives water its strange properties, vital for many chemical and biological processes July 8th, 2022

University of Oklahoma scientist’s quantum technology work garners international attention February 11th, 2022

Examining recent developments in quantum chromodynamics: A new collection looks at recent development in the field of quantum chromodynamics from a range of perspectives December 24th, 2021

Putting a new theory of many-particle quantum systems to the test: Experiments show that generalized hydrodynamics accurately simulates an out-of-equilibrium quantum system September 3rd, 2021

Govt.-Legislation/Regulation/Funding/Policy

Drawing data in nanometer scale September 30th, 2022

New technique allows researchers to scrape beyond the surface of nanomaterials: Using a new secondary-ion mass spectrometry technique, research are getting a fresh look at MXenes and MAX phases September 23rd, 2022

Solvent study solves solar cell durability puzzle: Rice-led project could make perovskite cells ready for prime time September 23rd, 2022

Heat-resistant nanophotonic material could help turn heat into electricity: The key to beating the heat is degrading the materials in advance September 23rd, 2022

Possible Futures

Researchers unveil mystery inside Li- o2 batteries September 30th, 2022

Synthesis of air-stable room-temperature van der Waals magnetic thin flakes September 30th, 2022

Layer Hall effect and hidden Berry curvature in antiferromagnetic insulators September 30th, 2022

ACM Research Launches New Furnace Tool for Thermal Atomic Layer Deposition to Support Advanced Semiconductor Manufacturing Requirements: Ultra Fn A Furnace Tool Shipped to China-Based Foundry Customer September 30th, 2022

Chip Technology

Conformal optical black hole for cavity September 30th, 2022

Synthesis of air-stable room-temperature van der Waals magnetic thin flakes September 30th, 2022

ACM Research Launches New Furnace Tool for Thermal Atomic Layer Deposition to Support Advanced Semiconductor Manufacturing Requirements: Ultra Fn A Furnace Tool Shipped to China-Based Foundry Customer September 30th, 2022

Key element for a scalable quantum computer: Physicists from Forschungszentrum Jülich and RWTH Aachen University demonstrate electron transport on a quantum chip September 23rd, 2022

Discoveries

Surface microstructures of lunar soil returned by Chang’e-5 mission reveal an intermediate stage in space weathering process September 30th, 2022

Researchers unveil mystery inside Li- o2 batteries September 30th, 2022

Synthesis of air-stable room-temperature van der Waals magnetic thin flakes September 30th, 2022

Layer Hall effect and hidden Berry curvature in antiferromagnetic insulators September 30th, 2022

Materials/Metamaterials

New technique allows researchers to scrape beyond the surface of nanomaterials: Using a new secondary-ion mass spectrometry technique, research are getting a fresh look at MXenes and MAX phases September 23rd, 2022

Wrapping of nanosize copper cubes can help convert carbon dioxide into other chemicals September 23rd, 2022

Upgrading your computer to quantum September 23rd, 2022

Digging a little deeper: New Earth Science Frontiers study explores the nanoscale properties of the Gulong shale oil reservoir: A new study elucidates the role of nanoscopic spaces in the in situ accumulation of shale oil in the Gulong-Qingshankou reservoir in China September 9th, 2022

Announcements

Researchers unveil mystery inside Li- o2 batteries September 30th, 2022

Synthesis of air-stable room-temperature van der Waals magnetic thin flakes September 30th, 2022

Layer Hall effect and hidden Berry curvature in antiferromagnetic insulators September 30th, 2022

ACM Research Launches New Furnace Tool for Thermal Atomic Layer Deposition to Support Advanced Semiconductor Manufacturing Requirements: Ultra Fn A Furnace Tool Shipped to China-Based Foundry Customer September 30th, 2022

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

Conformal optical black hole for cavity September 30th, 2022

Cleveland researchers reveal new strategy to prevent blood clots without increasing the risk of bleeding: University Hospitals and Case Western Reserve University findings may be especially impactful for cancer patients who experience blood clot complications September 30th, 2022

Ultrasmall VN/Co heterostructure with optimized N active sites anchored in N-doped graphitic nanocarbons for boosting hydrogen evolution September 30th, 2022

Layer Hall effect and hidden Berry curvature in antiferromagnetic insulators September 30th, 2022

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

Drawing data in nanometer scale September 30th, 2022

Multi-institution, $4.6 million NSF grant to fund nanotechnology training September 9th, 2022

Scientists take control of magnetism at the microscopic level: Neutrons reveal remarkable atomic behavior in thermoelectric materials for more efficient conversion of heat into electricity August 26th, 2022

Understanding outsize role of nanopores: New research reveals differences in pH, and more, about these previously mysterious environments August 26th, 2022

Quantum nanoscience

Upgrading your computer to quantum September 23rd, 2022

Key element for a scalable quantum computer: Physicists from Forschungszentrum Jülich and RWTH Aachen University demonstrate electron transport on a quantum chip September 23rd, 2022

Lattice distortion of perovskite quantum dots induces coherent quantum beating September 9th, 2022

Master equation to boost quantum technologies: FQXi-funded analysis will help physicists exert exquisitely precise real-time feedback control over quantum systems August 26th, 2022

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