Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Mind the gap: Nanoscale speed bump could regulate plasmons for high-speed data flow

02.04.2015

The name sounds like something Marvin the Martian might have built, but the "nanomechanical plasmonic phase modulator" is not a doomsday device.

Developed by a team of government and university researchers, including physicists from the National Institute of Standards and Technology (NIST), the innovation harnesses tiny electron waves called plasmons. It's a step towards enabling computers to process information hundreds of times faster than today's machines.


The plasmonic phase modulator is an inverted, nanoscale speed bump. Gold strands are stretched side by side across a gap just 270 nanometers above the gold surface below them. Incoming plasmons travel though this air gap between the bridges and the bottom gold layer. Lowering the

Credit: Dennis/Rutgers and Dill/NIST

Computers currently shuttle information around using electricity traveling down nanoscale metal wires. Although inexpensive and easy to miniaturize, metal wires are limited in terms of speed due to the resistance in the metal itself.

Fiber optics use light to move information about 10,000 times faster, but these and other nonmetallic waveguides are constrained by pesky physical laws that require critical dimensions to be at least half the wavelength of the light in size; still small, but many times larger than the dimensions of current commercial nanoscale electronics.

Plasmonics combines the small size and manufacturability of electronics with the high speeds of optics. When light waves interact with electrons on a metal's surface, strong fields with dimensions far smaller than the wavelength of the original light can be created--plasmons. Unlike light, these plasmons are free to travel down nanoscale wires or gaps in metals.

The team, which included researchers from Rutgers, the University of Colorado at Colorado Springs, and Argonne National Laboratory, fabricated their device using commercial nanofabrication equipment at the NIST NanoFab. Small enough to serve in existing and future computer architectures, this technology may also enable electrically tunable and switchable thin optical components.

Their findings were published in Nature Photonics.

The plasmonic phase modulator is effectively an inverted, nanoscale speed bump. Eleven gold strands are stretched side by side like footbridges across a 23-micrometer gap just 270 nanometers above the gold surface below them. Incoming plasmons, created by laser light at one end of the array, travel though this air gap between the bridges and the bottom gold layer.

When a control voltage is applied, electrostatic attraction bends the gold strands downwards into a U shape. At a maximum voltage--close to the voltages used in today's computer chips--the gap narrows, slowing the plasmons. As the plasmons slow, their wavelength becomes shorter, allowing more than an extra half of a plasmonic wave to fit under the bridge. Because it's exactly out of phase with the original wave, this additional half wavelength can be used to selectively cancel the wave, making the bridge an optical switch.

At 23 micrometers, the prototype is relatively large, but according to NIST researcher Vladimir Aksyuk, their calculations show that the device could be shortened by a factor of 10, scaling the device's footprint down by a factor of 100. According to these calculations, the modulation range can be maintained without increase in the optical loss, as the length and the size of the gap are reduced.

"With these prototypes, we showed that nanomechanical phase tuning is efficient," says Aksyuk. "This effect can be generalized to other tunable plasmonic devices that need to be made smaller. And as they get smaller, you can put more of them on the same chip, bringing them closer to practical realization."

###

B.S. Dennis, M.I. Haftel, D.A. Czaplewski, D. Lopez, G. Blumberg and V.A. Aksyuk. Compact nano-mechanical plasmonic phase modulators. Nature Photonics. Available online March 30. 2015.

Media Contact

Mark Esser
mark.esser@nist.gov
301-975-8735

 @usnistgov

http://www.nist.gov

Mark Esser | EurekAlert!

More articles from Physics and Astronomy:

nachricht Long-lived storage of a photonic qubit for worldwide teleportation
12.12.2017 | Max-Planck-Institut für Quantenoptik

nachricht Telescopes team up to study giant galaxy
12.12.2017 | International Centre for Radio Astronomy Research

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: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

Im Focus: Successful Mechanical Testing of Nanowires

With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong

Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Long-lived storage of a photonic qubit for worldwide teleportation

12.12.2017 | Physics and Astronomy

Multi-year submarine-canyon study challenges textbook theories about turbidity currents

12.12.2017 | Earth Sciences

Electromagnetic water cloak eliminates drag and wake

12.12.2017 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>