Nanotechnology Now

Our NanoNews Digest Sponsors
Heifer International

Wikipedia Affiliate Button

Home > Press > Quantum chains in graphene nanoribbons: Breakthrough in nanoresearch

When graphene nanoribbons contain sections of varying width, very robust new quantum states can be created in the transition zone.

CREDIT
Empa
When graphene nanoribbons contain sections of varying width, very robust new quantum states can be created in the transition zone. CREDIT Empa

Abstract:
A material that consists of atoms of a single element, but has completely different properties depend-ing on the atomic arrangement - this may sound strange, but is actually reality with graphene nano-ribbons. The ribbons, which are only a few carbon atoms wide and exactly one atom thick, have very different electronic properties depending on their shape and width: conductor, semiconductor or insu-lator. An international research team led by Empa's

Quantum chains in graphene nanoribbons: Breakthrough in nanoresearch

St. Gallen, Switzerland | Posted on August 9th, 2018

laboratory has now suc-ceeded in precisely adjusting the properties of the ribbons by specifically varying their shape. The par-ticular feature of this technology is that not only can the «usual» electronic properties mentioned above be varied - it can also be used to generate specific local quantum states.
So what's behind it? If the width of a narrow graphene nanoribbon changes, in this case from seven to nine atoms, a special zone is created at the transition: because the electronic properties of the two ar-eas differ in a special, so-called topological way, a «protected» and thus very robust new quantum state is created in the transition zone. This local electronic quantum state can now be used as a basic component to produce tailor-made semiconductors, metals or insulators - and possibly even as a component in quantum computers.

The Empa researchers under the lead of Oliver Gröning were able to show that if these ribbons are built with regularly alternating zones of different widths, a chain of interlinked quantum states with its own electronic structure is created by the numerous transitions. The exciting thing is that the electronic properties of the chain change depending on the width of the different segments. This allows them to be finely adjusted - from conductors to semiconductors with different bandgaps. This principle can be applied to many different types of transition zones - for example, from seven to eleven atoms.

«The importance of this development is also underlined by the fact that a research group at the Uni-versity of California, Berkeley, came to similar results independently of us,» said Gröning. The work of the US research team has been published in the same issue of Nature.

On the way to nanoelectronics

Based on these novel quantum chains, precise nano-transistors could be manufactured in the future - a fundamental step on the way to nanoelectronics. Whether the switching distance between the «1» state and the «0» state of the nanotransistor is actually large enough depends on the bandgap of the semiconductor - and with the new method this can be set almost at will.

In reality, however, this is not quite as simple: for the chain to have the desired electronic properties, each of the several hundred or even thousands of atoms must be in the right place. «This is based on complex, interdisciplinary research, » says Empa researcher Gröning. «Researchers from different disci-plines in Dübendorf, Mainz, Dresden, and Troy (USA) worked together - from theoretical understanding and specific knowledge of how precursor molecules have to be built and how structures on surfaces can be selectively grown to structural and electronic analysis using a scanning tunneling microscope.»

An excursion into the quantum realm

Ultrasmall transistors - and thus the next step in the further miniaturization of electronic circuits - are the obvious application possibilities here: although they are technically challenging, electronics based on nano-transistors actually work fundamentally the same as today's microelectronics. The semicon-ducting nanoribbons produced by the Empa researchers would allow transistors with a channel cross-section 1,000 times smaller than typically manufactured today. However, further possibilities can also be imagined, for example in the field of spintronics or even quantum informatics.

This is because the electronic quantum states at junctions of graphene nanoribbons of different widths can also carry a magnetic moment. This could make it possible to process information not by charge as was previously customary, but by the so-called spin - in the figurative sense the «direction of rota-tion» of the state. And the development could even go one step further. «We have observed that topological end states occur at the ends of certain quantum chains. This offers the possibility of using them as elements of so-called qubits - the complex, interlocked states in a quantum computer,» ex-plains Oliver Gröning.

Today and tomorrow, however, no quantum computer is built from nanoribbons - there is still a lot of research needed, says Gröning: «The possibility of flexibly adjusting the electronic properties through the targeted combination of individual quantum states represents a major leap for us in the production of new materials for ultra-miniaturized transistors.» The fact that these materials are stable under environmental conditions plays an important role in the development of future applications. "The further-reaching potential of the chains to create local quantum states and link them together in a targeted manner is also fascinating," Gröning continues. «Whether this potential can actually be ex-ploited for future quantum computers remains to be seen, however. It is not enough to create localized topological states in the nanoribbons - these would also have to be coupled with other materials such as superconductors in such a way that the conditions for qubits are actually met.»

####

For more information, please click here

Contacts:
Dr. Oliver Gröning

41-587-654-669

Copyright © EMPA

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

RELATED JOURNAL ARTICLE:

Related News Press

News and information

Engineers produce a fisheye lens that's completely flat: The single piece of glass produces crisp panoramic images September 22nd, 2020

New design principles for spin-based quantum materials: Criteria for designing targeted quantum materials could support Internet of Things devices and other resource-intensive technologies September 20th, 2020

Shape matters for light-activated nanocatalysts - Study: Pointed tips on aluminum 'octopods' increase catalytic reactivity September 18th, 2020

Aberrant electronic and structural alterations in pressure tuned perovskite NaOsO3 September 18th, 2020

Shedding Light on the Development of Efficient Blue-Emitting Semiconductors September 18th, 2020

Quantum Physics

New design principles for spin-based quantum materials: Criteria for designing targeted quantum materials could support Internet of Things devices and other resource-intensive technologies September 20th, 2020

Quirky response to magnetism presents quantum physics mystery: Magnetic topological insulators could be just right for making qubits, but this one doesn't obey the rules September 11th, 2020

Get diamonds, take temperature: Quantum thermometer using nanodiamonds senses a 'fever' in tiny worms C. elegans September 11th, 2020

2 Dimensional Materials

Nano-microscope gives first direct observation of the magnetic properties of 2D materials: Discovery means new class of materials and technologies September 18th, 2020

Understanding electron transport in graphene nanoribbons: New understanding of the electrical properties of graphene nanoribbons (GRBs), when bounded with aromatic molecules, could have significant benefits in the development of chemosensors and personalized medicine September 11th, 2020

Laboratories

Quirky response to magnetism presents quantum physics mystery: Magnetic topological insulators could be just right for making qubits, but this one doesn't obey the rules September 11th, 2020

Boundaries no barrier for thermoelectricity: Rice researchers find potentially useful electrical phenomenon in gold nanowires September 8th, 2020

Painting With Light: Novel Nanopillars Precisely Control the Color and Intensity of Transmitted Light September 4th, 2020

Graphene/ Graphite

Understanding electron transport in graphene nanoribbons: New understanding of the electrical properties of graphene nanoribbons (GRBs), when bounded with aromatic molecules, could have significant benefits in the development of chemosensors and personalized medicine September 11th, 2020

Possible Futures

Engineers produce a fisheye lens that's completely flat: The single piece of glass produces crisp panoramic images September 22nd, 2020

New design principles for spin-based quantum materials: Criteria for designing targeted quantum materials could support Internet of Things devices and other resource-intensive technologies September 20th, 2020

Shape matters for light-activated nanocatalysts - Study: Pointed tips on aluminum 'octopods' increase catalytic reactivity September 18th, 2020

Aberrant electronic and structural alterations in pressure tuned perovskite NaOsO3 September 18th, 2020

Chip Technology

New design principles for spin-based quantum materials: Criteria for designing targeted quantum materials could support Internet of Things devices and other resource-intensive technologies September 20th, 2020

Nano-microscope gives first direct observation of the magnetic properties of 2D materials: Discovery means new class of materials and technologies September 18th, 2020

Physicists make electrical nanolasers even smaller September 18th, 2020

FEFU scientists are paving way for future tiny electronics and gadgets August 28th, 2020

Quantum Computing

Quirky response to magnetism presents quantum physics mystery: Magnetic topological insulators could be just right for making qubits, but this one doesn't obey the rules September 11th, 2020

Oxford Instruments partners with the £10 million consortium, to launch the first commercial quantum computer in UK September 2nd, 2020

UCLA computer scientists set benchmarks to optimize quantum computer performance August 14th, 2020

When Dirac meets frustrated magnetism August 3rd, 2020

Nanoelectronics

FEFU scientists are paving way for future tiny electronics and gadgets August 28th, 2020

Oriented hexagonal boron nitride foster new type of information carrier May 22nd, 2020

A new strategy to create 2D magnetic order April 10th, 2020

Double-walled nanotubes have electro-optical advantages :Rice University calculations show they could be highly useful for solar panels March 27th, 2020

Discoveries

Engineers produce a fisheye lens that's completely flat: The single piece of glass produces crisp panoramic images September 22nd, 2020

New design principles for spin-based quantum materials: Criteria for designing targeted quantum materials could support Internet of Things devices and other resource-intensive technologies September 20th, 2020

Shape matters for light-activated nanocatalysts - Study: Pointed tips on aluminum 'octopods' increase catalytic reactivity September 18th, 2020

Aberrant electronic and structural alterations in pressure tuned perovskite NaOsO3 September 18th, 2020

Materials/Metamaterials

New design principles for spin-based quantum materials: Criteria for designing targeted quantum materials could support Internet of Things devices and other resource-intensive technologies September 20th, 2020

Nano-microscope gives first direct observation of the magnetic properties of 2D materials: Discovery means new class of materials and technologies September 18th, 2020

Aberrant electronic and structural alterations in pressure tuned perovskite NaOsO3 September 18th, 2020

Get diamonds, take temperature: Quantum thermometer using nanodiamonds senses a 'fever' in tiny worms C. elegans September 11th, 2020

Announcements

Engineers produce a fisheye lens that's completely flat: The single piece of glass produces crisp panoramic images September 22nd, 2020

New design principles for spin-based quantum materials: Criteria for designing targeted quantum materials could support Internet of Things devices and other resource-intensive technologies September 20th, 2020

Shape matters for light-activated nanocatalysts - Study: Pointed tips on aluminum 'octopods' increase catalytic reactivity September 18th, 2020

Aberrant electronic and structural alterations in pressure tuned perovskite NaOsO3 September 18th, 2020

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

Engineers produce a fisheye lens that's completely flat: The single piece of glass produces crisp panoramic images September 22nd, 2020

New design principles for spin-based quantum materials: Criteria for designing targeted quantum materials could support Internet of Things devices and other resource-intensive technologies September 20th, 2020

Physicists make electrical nanolasers even smaller September 18th, 2020

Shape matters for light-activated nanocatalysts - Study: Pointed tips on aluminum 'octopods' increase catalytic reactivity September 18th, 2020

Research partnerships

Gentle probes could enable massive brain data collection: National Institutes of Health backing Rice’s Chong Xie to refine flexible nanoelectronics thread September 14th, 2020

Boundaries no barrier for thermoelectricity: Rice researchers find potentially useful electrical phenomenon in gold nanowires September 8th, 2020

CEA-Leti X-Ray Photon-Counting Detector Modules Target Improved Medical Diagnoses: Clinical Trials Show Higher Spatial Resolution, Less Noise, Fewer Artifacts, And Color Capabilities in Patients’ Images September 3rd, 2020

Oxford Instruments partners with the £10 million consortium, to launch the first commercial quantum computer in UK September 2nd, 2020

Quantum nanoscience

New design principles for spin-based quantum materials: Criteria for designing targeted quantum materials could support Internet of Things devices and other resource-intensive technologies September 20th, 2020

Quirky response to magnetism presents quantum physics mystery: Magnetic topological insulators could be just right for making qubits, but this one doesn't obey the rules September 11th, 2020

Get diamonds, take temperature: Quantum thermometer using nanodiamonds senses a 'fever' in tiny worms C. elegans September 11th, 2020

Mathematical tool helps calculate properties of quantum materials more quickly August 14th, 2020

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