Nanotechnology Now

Our NanoNews Digest Sponsors


Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Natural 3D Counterpart to Graphene Discovered: Researchers at Berkeley Lab’s Advanced Light Source Find New Form of Quantum Matter

A topological Dirac semi-metal state is realized at the critical point in the phase transition from a normal insulator to a topological insulator. The + and – signs denote the even and odd parity of the energy bands.
A topological Dirac semi-metal state is realized at the critical point in the phase transition from a normal insulator to a topological insulator. The + and – signs denote the even and odd parity of the energy bands.

Abstract:
The discovery of what is essentially a 3D version of graphene - the 2D sheets of carbon through which electrons race at many times the speed at which they move through silicon - promises exciting new things to come for the high-tech industry, including much faster transistors and far more compact hard drives. A collaboration of researchers at the U.S Department of Energy (DOE)'s Lawrence Berkeley National Laboratory (Berkeley Lab) has discovered that sodium bismuthate can exist as a form of quantum matter called a three-dimensional topological Dirac semi-metal (3DTDS). This is the first experimental confirmation of 3D Dirac fermions in the interior or bulk of a material, a novel state that was only recently proposed by theorists.

Natural 3D Counterpart to Graphene Discovered: Researchers at Berkeley Lab’s Advanced Light Source Find New Form of Quantum Matter

Berkeley, CA | Posted on January 16th, 2014

"A 3DTDS is a natural three-dimensional counterpart to graphene with similar or even better electron mobility and velocity," says Yulin Chen, a physicist with Berkeley Lab's Advanced Light Source (ALS) when he initiated the study that led to this discovery, and now with the University of Oxford. "Because of its 3D Dirac fermions in the bulk, a 3DTDS also features intriguing non-saturating linear magnetoresistance that can be orders of magnitude higher than the materials now used in hard drives, and it opens the door to more efficient optical sensors."

Chen is the corresponding author of a paper in Science reporting the discovery. The paper is titled "Discovery of a Three-dimensional Topological Dirac Semimetal, Na3Bi." Co-authors were Zhongkai Liu, Bo Zhou, Yi Zhang, Zhijun Wang, Hongming Weng, Dharmalingam Prabhakaran, Sung-Kwan Mo, Zhi-Xun Shen, Zhong Fang, Xi Dai and Zahid Hussain.

Two of the most exciting new materials in the world of high technology today are graphene and topological insulators, crystalline materials that are electrically insulating in the bulk but conducting on the surface. Both feature 2D Dirac fermions (fermions that aren't their own antiparticle), which give rise to extraordinary and highly coveted physical properties. Topological insulators also possess a unique electronic structure, in which bulk electrons behave like those in an insulator while surface electrons behave like those in graphene.

"The swift development of graphene and topological insulators has raised questions as to whether there are 3D counterparts and other materials with unusual topology in their electronic structure," says Chen. "Our discovery answers both questions. In the sodium bismuthate we studied, the bulk conduction and valence bands touch only at discrete points and disperse linearly along all three momentum directions to form bulk 3D Dirac fermions. Furthermore, the topology of a 3DTSD electronic structure is also as unique as those of topological insulators."

The discovery was made at the Advanced Light Source (ALS), a DOE national user facility housed at Berkeley Lab, using beamline 10.0.1, which is optimized for electron structure studies. The collaborating research team first developed a special procedure to properly synthesize and transport the sodium bismuthate, a semi-metal compound identified as a strong 3DTDS candidate by co-authors Fang and Dai, theorists with the Chinese Academy of Sciences.

At ALS beamline 10.0.1, the collaborators determined the electronic structure of their material using Angle-Resolved Photoemission Spectroscopy (ARPES), in which x-rays striking a material surface or interface cause the photoemission of electrons at angles and kinetic energies that can be measured to obtain a detailed electronic spectrum.

"ALS beamline 10.0.1 is perfect for exploring new materials, as it has a unique capability whereby the analyzer is moved rather than the sample for the ARPES measurement scans," Chen says. "This made our work much easier as the cleaved sample surface of our material sometimes has multiple facets, which makes the rotating-sample measurement schemes typically employed for ARPES measurements difficult to carry out."

Sodium bismuthate is too unstable to be used in devices without proper packaging, but it triggers the exploration for the development of other 3DTDS materials more suitable for everyday devices, a search that is already underway. Sodium bismuthate can also be used to demonstrate potential applications of 3DTDS systems, which offer some distinct advantages over graphene.

"A 3DTDS system could provide a significant improvement in efficiency in many applications over graphene because of its 3D volume," Chen says. "Also, preparing large-size atomically thin single domain graphene films is still a challenge. It could be easier to fabricate graphene-type devices for a wider range of applications from 3DTDS systems."

In addition, Chen says, a 3DTDS system also opens the door to other novel physical properties, such as giant diamagnetism that diverges when energy approaches the 3D Dirac point, quantum magnetoresistance in the bulk, unique Landau level structures under strong magnetic fields, and oscillating quantum spin Hall effects. All of these novel properties can be a boon for future electronic technologies. Future 3DTDS systems can also serve as an ideal platform for applications in spintronics.

This research was supported by the DOE Office of Science and by the National Science Foundation of China.

####

About Berkeley Lab
Lawrence Berkeley National Laboratory addresses the world’s most urgent scientific challenges by advancing sustainable energy, protecting human health, creating new materials, and revealing the origin and fate of the universe. Founded in 1931, Berkeley Lab’s scientific expertise has been recognized with 13 Nobel prizes. The University of California manages Berkeley Lab for the U.S. Department of Energy’s Office of Science. For more, visit www.lbl.gov.

The Advanced Light Source is a third-generation synchrotron light source producing light in the x-ray region of the spectrum that is a billion times brighter than the sun. A DOE national user facility, the ALS attracts scientists from around the world and supports its users in doing outstanding science in a safe environment. For more information visit http://www.als.lbl.gov/.

DOE’s Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit the Office of Science website at science.energy.gov/.

For more information, please click here

Contacts:
Lynn Yarris

510-486-5375

Copyright © Berkeley Lab

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 News Press

News and information

Superheroes are real: Ultrasensitive nonlinear metamaterials for data transfer June 25th, 2016

Russian physicists create a high-precision 'quantum ruler': Physicists have devised a method for creating a special quantum entangled state June 25th, 2016

Nanoscientists develop the 'ultimate discovery tool': Rapid discovery power is similar to what gene chips offer biology June 25th, 2016

Ultrathin, flat lens resolves chirality and color: Multifunctional lens could replace bulky, expensive machines June 25th, 2016

Researchers discover new chemical sensing technique: Technique allows sharper detail -- and more information -- with near infrared light June 24th, 2016

Physics

Russian physicists create a high-precision 'quantum ruler': Physicists have devised a method for creating a special quantum entangled state June 25th, 2016

Particle zoo in a quantum computer: First experimental quantum simulation of particle physics phenomena June 23rd, 2016

Imaging

Ultrathin, flat lens resolves chirality and color: Multifunctional lens could replace bulky, expensive machines June 25th, 2016

Researchers discover new chemical sensing technique: Technique allows sharper detail -- and more information -- with near infrared light June 24th, 2016

Coexistence of superconductivity and charge density waves observed June 23rd, 2016

Soft decoupling of organic molecules on metal June 23rd, 2016

New electron microscope method detects atomic-scale magnetism June 22nd, 2016

Superconductivity

Coexistence of superconductivity and charge density waves observed June 23rd, 2016

Titan shines light on high-temperature superconductor pathway: Simulation demonstrates how superconductivity arises in cuprates' pseudogap phase June 22nd, 2016

Marrying superconductors, lasers, and Bose-Einstein condensates: Chapman University Institute for Quantum Studies (IQS) member Yutaka Shikano, Ph.D., recently had research published in Scientific Reports June 20th, 2016

Graphene/ Graphite

GraphExeter illuminates bright new future for flexible lighting devices June 23rd, 2016

Laboratories

Titan shines light on high-temperature superconductor pathway: Simulation demonstrates how superconductivity arises in cuprates' pseudogap phase June 22nd, 2016

Discovery of gold nanocluster 'double' hints at other shape-changing particles: New analysis approach brings two unique atomic structures into focus June 19th, 2016

Govt.-Legislation/Regulation/Funding/Policy

Nanoscientists develop the 'ultimate discovery tool': Rapid discovery power is similar to what gene chips offer biology June 25th, 2016

Ultrathin, flat lens resolves chirality and color: Multifunctional lens could replace bulky, expensive machines June 25th, 2016

Particle zoo in a quantum computer: First experimental quantum simulation of particle physics phenomena June 23rd, 2016

Titan shines light on high-temperature superconductor pathway: Simulation demonstrates how superconductivity arises in cuprates' pseudogap phase June 22nd, 2016

Spintronics

CWRU physicists deploy magnetic vortex to control electron spin: Potential technology for quantum computing, keener sensors June 21st, 2016

Spintronics: Resetting the future of heat assisted magnetic recording June 15th, 2016

Spintronics development gets boost with new findings into ferromagnetism in Mn-doped GaAs June 7th, 2016

Gigantic ultrafast spin currents: Scientists from TU Wien (Vienna) are proposing a new method for creating extremely strong spin currents. They are essential for spintronics, a technology that could replace today's electronics May 25th, 2016

Chip Technology

GraphExeter illuminates bright new future for flexible lighting devices June 23rd, 2016

Soft decoupling of organic molecules on metal June 23rd, 2016

Particle zoo in a quantum computer: First experimental quantum simulation of particle physics phenomena June 23rd, 2016

Nanometrics to Participate in the 8th Annual CEO Investor Summit: Investor Event Held Concurrently with SEMICON West 2016 in San Francisco June 22nd, 2016

Memory Technology

Ensuring the future affordability of wind turbines, computers and electric cars June 2nd, 2016

Automating DNA origami opens door to many new uses: Like 3-D printing did for larger objects, method makes it easy to build nanoparticles out of DNA May 30th, 2016

Hybrid nanoantennas -- next-generation platform for ultradense data recording April 28th, 2016

Magnetic vortices defy temperature fluctuations: Common magnetic mineral is reliable witness to Earth's history April 19th, 2016

Discoveries

Superheroes are real: Ultrasensitive nonlinear metamaterials for data transfer June 25th, 2016

Russian physicists create a high-precision 'quantum ruler': Physicists have devised a method for creating a special quantum entangled state June 25th, 2016

Nanoscientists develop the 'ultimate discovery tool': Rapid discovery power is similar to what gene chips offer biology June 25th, 2016

Ultrathin, flat lens resolves chirality and color: Multifunctional lens could replace bulky, expensive machines June 25th, 2016

Materials/Metamaterials

Superheroes are real: Ultrasensitive nonlinear metamaterials for data transfer June 25th, 2016

Coexistence of superconductivity and charge density waves observed June 23rd, 2016

GraphExeter illuminates bright new future for flexible lighting devices June 23rd, 2016

Soft decoupling of organic molecules on metal June 23rd, 2016

Announcements

Superheroes are real: Ultrasensitive nonlinear metamaterials for data transfer June 25th, 2016

Russian physicists create a high-precision 'quantum ruler': Physicists have devised a method for creating a special quantum entangled state June 25th, 2016

Nanoscientists develop the 'ultimate discovery tool': Rapid discovery power is similar to what gene chips offer biology June 25th, 2016

Ultrathin, flat lens resolves chirality and color: Multifunctional lens could replace bulky, expensive machines June 25th, 2016

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

Superheroes are real: Ultrasensitive nonlinear metamaterials for data transfer June 25th, 2016

Russian physicists create a high-precision 'quantum ruler': Physicists have devised a method for creating a special quantum entangled state June 25th, 2016

Nanoscientists develop the 'ultimate discovery tool': Rapid discovery power is similar to what gene chips offer biology June 25th, 2016

Ultrathin, flat lens resolves chirality and color: Multifunctional lens could replace bulky, expensive machines June 25th, 2016

Tools

Nanoscientists develop the 'ultimate discovery tool': Rapid discovery power is similar to what gene chips offer biology June 25th, 2016

Ultrathin, flat lens resolves chirality and color: Multifunctional lens could replace bulky, expensive machines June 25th, 2016

Researchers discover new chemical sensing technique: Technique allows sharper detail -- and more information -- with near infrared light June 24th, 2016

Coexistence of superconductivity and charge density waves observed June 23rd, 2016

Industrial

Industrial Nanotech, Inc. Signs Agreement With and Receives First Purchase Order from Major New Customer in China June 6th, 2016

GLOBALFOUNDRIES to Expand Presence in China with 300mm Fab in Chongqing: Company plans new manufacturing facility and additional design capabilities to serve customers in China May 31st, 2016

Finding a new formula for concrete: Researchers look to bones and shells as blueprints for stronger, more durable concrete May 26th, 2016

Solliance realizes first up-scaled Perovskite based PV modules with 10% efficiency: Holst Centre, imec and ECN pave the road to upscaling Perovskite PV modules May 10th, 2016

Research partnerships

Superheroes are real: Ultrasensitive nonlinear metamaterials for data transfer June 25th, 2016

Soft decoupling of organic molecules on metal June 23rd, 2016

FEI and University of Liverpool Announce QEMSCAN Research Initiative: University of Liverpool will utilize FEI’s QEMSCAN technology to gain a better insight into oil and gas reserves & potentially change the approach to evaluating them June 22nd, 2016

Tailored DNA shifts electrons into the 'fast lane': DNA nanowire improved by altering sequences June 22nd, 2016

Quantum nanoscience

CWRU physicists deploy magnetic vortex to control electron spin: Potential technology for quantum computing, keener sensors June 21st, 2016

Neutrons reveal unexpected magnetism in rare-earth alloy June 16th, 2016

Spintronics: Resetting the future of heat assisted magnetic recording June 15th, 2016

NIST's super quantum simulator 'entangles' hundreds of ions June 11th, 2016

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




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







Car Brands
Buy website traffic