Nanotechnology Now

Our NanoNews Digest Sponsors



Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > Nano-sized light mill drives micro-sized disk

This STM image shows a gammadion gold light mill nanomotor embedded in a silica microdisk. Inset is a magnified top view of the light mill.
This STM image shows a gammadion gold light mill nanomotor embedded in a silica microdisk. Inset is a magnified top view of the light mill.

Abstract:
While those wonderful light sabers in the Star Wars films remain the figment of George Lucas' fertile imagination, light mills - rotary motors driven by light - that can power objects thousands of times greater in size are now fact.

Nano-sized light mill drives micro-sized disk

Berkeley, CA | Posted on July 5th, 2010

Researchers with the U.S. Department of Energy (DOE)'s Lawrence Berkeley National Laboratory and the University of California (UC) Berkeley have created the first nano-sized light mill motor whose rotational speed and direction can be controlled by tuning the frequency of the incident light waves. It may not help conquer the Dark Side, but this new light mill does open the door to a broad range of valuable applications, including a new generation of nanoelectromechanical systems (NEMS), nanoscale solar light harvesters, and bots that can perform in vivo manipulations of DNA and other biological molecules.

"We have demonstrated a plasmonic motor only 100 nanometers in size that when illuminated with linearly polarized light can generate a torque sufficient to drive a micrometre-sized silica disk 4,000 times larger in volume," says Xiang Zhang, a principal investigator with Berkeley Lab's Materials Sciences Division and director of UC Berkeley's Nano-scale Science and Engineering Center (SINAM), who led this research. "In addition to easily being able to control the rotational speed and direction of this motor, we can create coherent arrays of such motors, which results in greater torque and faster rotation of the microdisk."

The success of this new light mill stems from the fact that the force exerted on matter by light can be enhanced in a metallic nanostructure when the frequencies of the incident light waves are resonant with the metal's plasmons - surface waves that roll through a metal's conduction electrons. Zhang and his colleagues fashioned a gammadion-shaped light mill type of nanomotor out of gold that was structurally designed to maximize the interactions between light and matter. The metamaterial-style structure also induced orbital angular momentum on the light that in turn imposed a torque on the nanomotor.

"The planar gammadion gold structures can be viewed as a combination of four small LC-circuits for which the resonant frequencies are determined by the geometry and dielectric properties of the metal," says Zhang. "The imposed torque results solely from the gammadion structure's symmetry and interaction with all incident light, including light which doesn't carry angular momentum. Essentially we use design to encode angular momentum in the structure itself. Since the angular momentum of the light need not be pre-determined, the illuminating source can be a simple linearly polarized plane-wave or Gaussian beam."

The results of this research are reported in the journal Nature Nanotechnology in a paper titled, " Light-driven nanoscale plasmonic motors." Co-authoring the paper with Zhang were Ming Liu, Thomas Zentgraf, Yongmin Liu and Guy Bartal.

It has long been known that the photons in a beam of light carry both linear and angular momentum that can be transferred to a material object. Optical tweezers and traps, for example, are based on the direct transfer of linear momentum. In 1936, Princeton physicist Richard Beth demonstrated that angular momentum - in either its spin or orbital form - when altered by the scattering or absorption of light can produce a mechanical torque on an object. Previous attempts to harness this transfer of angular momentum for a rotary motor have been hampered by the weakness of the interaction between photons and matter.

"The typical motors had to be at least micrometres or even millimeters in size in order to generate a sufficient amount of torque," says lead author Ming Liu, a PhD student in Zhang's group. "We've shown that in a nanostructure like our gammadion gold light mill, torque is greatly enhanced by the coupling of the incident light to plasmonic waves. The power density of our motors is very high. As a bonus, the rotational direction is controllable, a counterintuitive fact based on what we learn from wind mills."

The directional change, Liu explains, is made possible by the support of the four-armed gammadion structure for two major resonance modes - a wavelength of 810 nanometers, and a wavelength of 1,700 nanometers. When illuminated with a linearly polarized Gaussian beam of laser light at the shorter wavelength, the plasmonic motor rotated counterclockwise at a rate of 0.3 Hertz. When illuminated with a similar laser beam but at the larger wavelength, the nanomotor rotated at the same rate of speed but in a clockwise direction.

"When multiple motors are integrated into one silica microdisk, the torques applied on the disk from the individual motors accumulate and the overall torque is increased," Liu says. "For example, a silica disk embedded with four plasmonic nanomotors attains the same rotation speed with only half of the laser power applied as a disk embedded with a single motor."

The nanoscale size of this new light mill makes it ideal for powering NEMS, where the premium is on size rather than efficiency. Generating relatively powerful torque in a nanosized light mill also has numerous potential biological applications, including the controlled unwinding and rewinding of the DNA double helix. When these light mill motors are structurally optimized for efficiency, they could be useful for harvesting solar energy in nanoscopic systems.

"By designing multiple motors to work at different resonance frequencies and in a single direction, we could acquire torque from the broad range of wavelengths available in sunlight," Liu says.

This research was supported by DOE's Office of Science.


For more information about the research of Xiang Zhang visit xlab.me.berkeley.edu/xlabnews.htm

For more information about the Berkeley Nano-scale Science and Engineering Center visit www.sinam.org/


####

About Berkeley Lab
Berkeley Lab is a U.S. Department of Energy national laboratory located in Berkeley, California. It conducts unclassified scientific research for DOE’s Office of Science and is managed by the University of California. Visit our Website at www.lbl.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

Smallest possible diamonds form ultra-thin nanothreads: Diamond nanothreads are likely to have extraordinary properties, including strength and stiffness greater than that of today's strongest nanotubes and polymers September 22nd, 2014

Engineers show light can play seesaw at the nanoscale: Discovery is another step toward faster and more energy-efficient optical devices for computation and communication September 22nd, 2014

New chip promising for tumor-targeting research September 22nd, 2014

Twisted graphene chills out: When two sheets of graphene are stacked in a special way, it is possible to cool down the graphene with a laser instead of heating it up, University of Manchester researchers have shown September 22nd, 2014

NEMS

Carbyne morphs when stretched: Rice University calculations show carbon-atom chain would go metal to semiconductor July 21st, 2014

LetiDays Grenoble to Present Multiple Perspectives on Development, Challenges and Markets for the IoT April 14th, 2014

Columbia engineers make world's smallest FM radio transmitter: Team demonstrates new application of graphene using positive feedback November 18th, 2013

Revisiting quantum effects in MEMS: New calculations shows that the influence of quantum effects on the operating conditions of nanodevices has, until now, been overestimated November 15th, 2013

Govt.-Legislation/Regulation/Funding/Policy

Engineered proteins stick like glue — even in water: New adhesives based on mussel proteins could be useful for naval or medical applications September 22nd, 2014

Smallest possible diamonds form ultra-thin nanothreads: Diamond nanothreads are likely to have extraordinary properties, including strength and stiffness greater than that of today's strongest nanotubes and polymers September 22nd, 2014

Engineers show light can play seesaw at the nanoscale: Discovery is another step toward faster and more energy-efficient optical devices for computation and communication September 22nd, 2014

New chip promising for tumor-targeting research September 22nd, 2014

Possible Futures

Air Force’s 30-year plan seeks 'strategic agility' August 1st, 2014

IBM Announces $3 Billion Research Initiative to Tackle Chip Grand Challenges for Cloud and Big Data Systems: Scientists and engineers to push limits of silicon technology to 7 nanometers and below and create post-silicon future July 10th, 2014

Virus structure inspires novel understanding of onion-like carbon nanoparticles April 10th, 2014

Local girl does good March 22nd, 2014

Academic/Education

Biosensors Get a Boost from Graphene Partnership: $5 Million Investment Supports Dozens of Jobs and Development of 300mm Fabrication Process and Wafer Transfer Facility September 18th, 2014

Malvern technology delivers Malvern reliability in multi-disciplinary lab at Queen Mary University London September 9th, 2014

State University of New York Trustees Unanimously Approve SUNY Polytechnic Institute (SUNY Poly) as New Name for Merged SUNY CNSE / SUNYIT September 9th, 2014

New Vice President Takes Helm at CNSE CMOST: Catherine Gilbert To Lead CNSE Children’s Museum of Science and Technology Through Expansion And Relocation August 29th, 2014

Molecular Machines

Optimum inertial design for self-propulsion: A new study investigates the effects of small but finite inertia on the propulsion of micro and nano-scale swimming machines July 29th, 2014

Breakthrough laser experiment reveals liquid-like motion of atoms in an ultra-cold cluster: University of Leicester research team unlocks insights into creation of new nano-materials July 25th, 2014

NIST shows ultrasonically propelled nanorods spin dizzyingly fast July 22nd, 2014

University of Illinois researchers demonstrate novel, tunable nanoantennas July 14th, 2014

Nanomedicine

Engineered proteins stick like glue — even in water: New adhesives based on mussel proteins could be useful for naval or medical applications September 22nd, 2014

New chip promising for tumor-targeting research September 22nd, 2014

Arrowhead to Present at BioCentury's NewsMakers in the Biotech Industry Conference September 19th, 2014

The Pocket Project will develop a low-cost and accurate point-of-care test to diagnose Tuberculosis: ICN2 holds a follow-up meeting of the Project on September 18th - 19th September 18th, 2014

Announcements

Engineers show light can play seesaw at the nanoscale: Discovery is another step toward faster and more energy-efficient optical devices for computation and communication September 22nd, 2014

New chip promising for tumor-targeting research September 22nd, 2014

Twisted graphene chills out: When two sheets of graphene are stacked in a special way, it is possible to cool down the graphene with a laser instead of heating it up, University of Manchester researchers have shown September 22nd, 2014

New star-shaped molecule breakthrough: Scientists at The University of Manchester have generated a new star-shaped molecule made up of interlocking rings, which is the most complex of its kind ever created September 22nd, 2014

Nanobiotechnology

New star-shaped molecule breakthrough: Scientists at The University of Manchester have generated a new star-shaped molecule made up of interlocking rings, which is the most complex of its kind ever created September 22nd, 2014

Arrowhead to Present at BioCentury's NewsMakers in the Biotech Industry Conference September 19th, 2014

CiQUS researchers design an artificial nose to detect DNA differentiation with single nucleotide resolution September 18th, 2014

Biosensors Get a Boost from Graphene Partnership: $5 Million Investment Supports Dozens of Jobs and Development of 300mm Fabrication Process and Wafer Transfer Facility September 18th, 2014

Research partnerships

Biosensors Get a Boost from Graphene Partnership: $5 Million Investment Supports Dozens of Jobs and Development of 300mm Fabrication Process and Wafer Transfer Facility September 18th, 2014

The Pocket Project will develop a low-cost and accurate point-of-care test to diagnose Tuberculosis: ICN2 holds a follow-up meeting of the Project on September 18th - 19th September 18th, 2014

Recruiting bacteria to be technology innovation partners: September 17th, 2014

Carbon Sciences Developing Breakthrough Technology to Mass-Produce Graphene -- the New Miracle Material: Company Enters Into an Agreement With the University of California, Santa Barbara (UCSB) to Fund the Further Development of a New Graphene Process September 16th, 2014

Solar/Photovoltaic

Simple, Cost-Effective Method Proposed for Synthesizing Zinc Oxide Nanopigments September 15th, 2014

Indium/Copper Sulfide Compound Semi-Conductor Synthesized through New Method September 8th, 2014

Material development on the nanoscale: Doped graphene nanoribbons with potential September 8th, 2014

Layered graphene sandwich for next generation electronics September 8th, 2014

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







© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE