Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Atomically Thin Material Gets Excited From Afar, Opening a Door for Integrated Nanophotonic Circuits

08.09.2014

A new combination of materials can efficiently guide electricity and light along the same tiny wire, a finding that could be a step towards building computer chips capable of transporting digital information at the speed of light.

Reporting today in The Optical Society’s (OSA) high-impact journal Optica, optical and material scientists at the University of Rochester and Swiss Federal Institute of Technology in Zurich describe a basic model circuit consisting of a silver nanowire and a single-layer flake of molybdenum disulfide (MoS2).


Illustration by Michael Osadciw, Creative Services, University of Rochester

Far-field photons excite silver nanowire plasmons. The wire plasmons propagate to the wire's distal end where they efficiently interact with the two-dimensional material semiconductor molybdenum disulfide (MoS2). The plasmons are absorbed in the MoS2 creating excitons that subsequently decay converting back into propagating photons.

Using a laser to excite electromagnetic waves called plasmons at the surface of the wire, the researchers found that the MoS2 flake at the far end of the wire generated strong light emission. Going in the other direction, as the excited electrons relaxed, they were collected by the wire and converted back into plasmons, which emitted light of the same wavelength.

“We have found that there is pronounced nanoscale light-matter interaction between plasmons and atomically thin material that can be exploited for nanophotonic integrated circuits,” said Nick Vamivakas, assistant professor of quantum optics and quantum physics at the University of Rochester and senior author of the paper.

Typically about a third of the remaining energy would be lost for every few microns (millionths of a meter) the plasmons traveled along the wire, explained Kenneth Goodfellow, a graduate student at Rochester’s Institute of Optics and lead author of the Optica paper.

“It was surprising to see that enough energy was left after the round-trip,” said Goodfellow.

Photonic devices can be much faster than electronic ones, but they are bulkier because devices that focus light cannot be miniaturized nearly as well as electronic circuits, said Goodfellow. The new results hold promise for guiding the transmission of light, and maintaining the intensity of the signal, in very small dimensions.

Ever since the discovery of graphene, a single layer of carbon that can be extracted from graphite with adhesive tape, scientists have been rapidly exploring the world of two-dimensional materials. These materials have unique properties not seen in their bulk form.

Like graphene, MoS2 is made up of layers that are weakly bonded to each other, so they can be easily separated. In bulk MoS2, electrons and photons interact as they would in traditional semiconductors like silicon and gallium arsenide. As MoS2 is reduced to thinner and thinner layers, the transfer of energy between electrons and photons becomes more efficient.

The key to MoS2’s desirable photonic properties is in the structure of its energy band gap. As the material’s layer count decreases, it transitions from an indirect to direct band gap, which allows electrons to easily move between energy bands by releasing photons. Graphene is inefficient at light emission because it has no band gap.

Combining electronics and photonics on the same integrated circuits could drastically improve the performance and efficiency of mobile technology. The researchers say the next step is to demonstrate their primitive circuit with light emitting diodes.

Paper: K. Goodfellow, R. Beams, C. Chakraborty, L. Novotny, A.N. Vamivakas “Integrated nanophotonics based on nanowire plasmons and atomically-thin material” Optica Vol. 1, Issue 3, pp.149-152 (2014).

About the University of Rochester
The University of Rochester (www.rochester.edu) is one of the nation’s leading private universities. Located in Rochester, N.Y., the University gives students exceptional opportunities for interdisciplinary study and close collaboration with faculty through its unique cluster-based curriculum. Its College, School of Arts and Sciences, and Hajim School of Engineering and Applied Sciences are complemented by its Eastman School of Music, Simon School of Business, Warner School of Education, Laboratory for Laser Energetics, School of Medicine and Dentistry, School of Nursing, Eastman Institute for Oral Health, and the Memorial Art Gallery.

Contact Information

David Barnstone
dbarnsto@ur.rochester.edu
585.276.6264

David Barnstone | newswise

Further reports about: Atomically Circuits Door MoS2 Thin circuit electrons graphene materials nanowire photons properties

More articles from Physics and Astronomy:

nachricht Electronic evidence of non-Fermi liquid behaviors in an iron-based superconductor
11.12.2018 | Science China Press

nachricht Physicists edge closer to controlling chemical reactions
11.12.2018 | Moscow Institute of Physics and Technology

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Topological material switched off and on for the first time

Key advance for future topological transistors

Over the last decade, there has been much excitement about the discovery, recognised by the Nobel Prize in Physics only two years ago, that there are two types...

Im Focus: Researchers develop method to transfer entire 2D circuits to any smooth surface

What if a sensor sensing a thing could be part of the thing itself? Rice University engineers believe they have a two-dimensional solution to do just that.

Rice engineers led by materials scientists Pulickel Ajayan and Jun Lou have developed a method to make atom-flat sensors that seamlessly integrate with devices...

Im Focus: Three components on one chip

Scientists at the University of Stuttgart and the Karlsruhe Institute of Technology (KIT) succeed in important further development on the way to quantum Computers.

Quantum computers one day should be able to solve certain computing problems much faster than a classical computer. One of the most promising approaches is...

Im Focus: Substitute for rare earth metal oxides

New Project SNAPSTER: Novel luminescent materials by encapsulating phosphorescent metal clusters with organic liquid crystals

Nowadays energy conversion in lighting and optoelectronic devices requires the use of rare earth oxides.

Im Focus: A bit of a stretch... material that thickens as it's pulled

Scientists have discovered the first synthetic material that becomes thicker - at the molecular level - as it is stretched.

Researchers led by Dr Devesh Mistry from the University of Leeds discovered a new non-porous material that has unique and inherent "auxetic" stretching...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

New Plastics Economy Investor Forum - Meeting Point for Innovations

10.12.2018 | Event News

EGU 2019 meeting: Media registration now open

06.12.2018 | Event News

Expert Panel on the Future of HPC in Engineering

03.12.2018 | Event News

 
Latest News

Electronic evidence of non-Fermi liquid behaviors in an iron-based superconductor

11.12.2018 | Physics and Astronomy

Topological material switched off and on for the first time

11.12.2018 | Materials Sciences

NIST's antenna evaluation method could help boost 5G network capacity and cut costs

11.12.2018 | Information Technology

VideoLinks
Science & Research
Overview of more VideoLinks >>>