Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Penn engineers' nanoantennas improve infrared sensing

A diagram showing how the researchers' optomechanical infrared-detecting structure works.
A diagram showing how the researchers' optomechanical infrared-detecting structure works.

Abstract:
A team of University of Pennsylvania engineers has used a pattern of nanoantennas to develop a new way of turning infrared light into mechanical action, opening the door to more sensitive infrared cameras and more compact chemical-analysis techniques.

Penn engineers' nanoantennas improve infrared sensing

Philadelphia, PA | Posted on May 20th, 2013

The research was conducted by assistant professor Ertugrul Cubukcu and postdoctoral researcher Fei Yi, along with graduate students Hai Zhu and Jason C. Reed, all of the Department of Material Science and Engineering in Penn's School of Engineering and Applied Science.

It was published in the journal Nano Letters.

Detecting light in the mid-infrared range is important for applications like night-vision cameras, but it can also be used to do spectroscopy, a technique that involves scattering light over a substance to infer its chemical composition. Existing infrared detectors use cryogenically cooled semiconductors, or thermal detectors known as microbolometers, in which changes in electrical resistance can be correlated to temperatures. These techniques have their own advantages, but both need expensive, bulky equipment to be sensitive enough for spectroscopy applications.

"We set out to make an optomechanical thermal infrared detector," Cubukcu said. "Rather than changes in resistance, our detector works by connecting mechanical motion to changes in temperature."

The advantage to this approach is that it could reduce the footprint of an infrared sensing device to something that would fit on a disposable silicon chip. The researchers fabricated such a device in their study.

At the core of the device is a nanoscale structure — about a tenth of a millimeter wide and five times as long — made of a layer of gold bonded to a layer of silicon nitride. The researchers chose these materials because of their different thermal expansion coefficients, a parameter that determines how much a material will expand when heated. Because metals will naturally convert some energy from infrared light into heat, researchers can connect the amount the material expands to the amount of infrared light hitting it.

"A single layer would expand laterally, but our two layers are constrained because they're attached to one another," Cubukcu said. "The only way they can expand is in the third dimension. In this case, that means bending toward the gold side, since gold has the higher thermal expansion coefficient and will expand more."

To measure this movement, the researchers used a fiber interferometer. A fiber optic cable pointed upward at this system bounces light off the underside of the silicon nitride layer, enabling the researchers to determine how far the structure has bent upwards.

"We can tell how far the bottom layer has moved based on this reflected light," Cubukcu said. "We can even see displacements that are thousands of times smaller than a hydrogen atom."

Other researchers have developed optomechanical infrared sensors based on this principle, but their sensitivities have been comparatively low. The Penn team's device is an improvement in this regard due to the inclusion of "slot" nanoantennas, cavities that are etched into the gold layer at intervals that correspond to wavelengths of mid-infrared light.

"The infrared radiation is concentrated into the slots, so you don't need any additional material to make these antennas," Cubukcu said. "We take the same exact platform and, by patterning it with these nanoscale antennas, the conversion efficiency of the detector improves 10 times."

The inclusion of nanoantennas provides the device with an additional advantage: the ability to tailor which type of light it is sensitive to by etching a different pattern of slots on the surface.

"Other techniques can only work at the maximum absorption determined by the material itself," Yi said. "Our antennas can be engineered to absorb at any wavelength."

While only a proof-of-concept at this stage, future research will demonstrate the device's capabilities as a low-cost way of analyzing individual proteins and gas molecules.

The research was supported by the National Science Foundation, Penn's Materials Research Science and Engineering Center, Penn's Nano/Bio Interface Center and the Penn Regional Nanotechnology Facility.

####

For more information, please click here

Contacts:
Evan Lerner

215-573-6604

Copyright © University of Pennsylvania

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

Geoffrey Beach: Drawn to explore magnetism: Materials researcher is working on the magnetic memory of the future April 25th, 2017

Using light to propel water : With new method, MIT engineers can control and separate fluids on a surface using only visible light April 25th, 2017

Graphene holds up under high pressure: Used in filtration membranes, ultrathin material could help make desalination more productive April 24th, 2017

Nanoparticle vaccine shows potential as immunotherapy to fight multiple cancer types April 24th, 2017

Chemistry

Shedding light on the absorption of light by titanium dioxide April 14th, 2017

Researchers uncover secret of nanomaterial that makes harvesting sunlight easier March 29th, 2017

Promising results obtained with a new electrocatalyst that reduces the need for platinum: Researchers from Aalto University have succeeded in manufacturing electrocatalysts used for storing electric energy with one-hundredth of the amount of platinum that is usually needed March 24th, 2017

Researchers develop groundbreaking process for creating ultra-selective separation membranes: Discovery could greatly improve energy-efficiency of separation and purification processes in the chemical and petrochemical industries March 15th, 2017

Imaging

Nanoparticles open new window for biological imaging: “Quantum dots” that emit infrared light enable highly detailed images of internal body structures April 10th, 2017

The Catholic University of Rome uses the JPK NanoWizard® AFM & CellHesion® systems to understand how cells sense and respond to mechanical stimuli April 5th, 2017

Tiny sensor lays groundwork for precision X-rays detection via endoscopy:Nanoscale fiber-integrated X-ray sensor opens new doors for medical imaging and radiotherapy March 29th, 2017

Cryo-electron microscopy achieves unprecedented resolution using new computational methods March 25th, 2017

Lab-on-a-chip

Researchers make flexible glass for tiny medical devices: Glass can bend over and over again on a nanoscale March 27th, 2017

Govt.-Legislation/Regulation/Funding/Policy

Graphene holds up under high pressure: Used in filtration membranes, ultrathin material could help make desalination more productive April 24th, 2017

Nanoparticle vaccine shows potential as immunotherapy to fight multiple cancer types April 24th, 2017

NanoMONITOR shares its latest developments concerning the NanoMONITOR Software and the Monitoring stations April 21st, 2017

Better living through pressure: Functional nanomaterials made easy April 19th, 2017

Chip Technology

Geoffrey Beach: Drawn to explore magnetism: Materials researcher is working on the magnetic memory of the future April 25th, 2017

'Neuron-reading' nanowires could accelerate development of drugs for neurological diseases April 12th, 2017

Nanometrics to Announce First Quarter Financial Results on May 2, 2017 April 11th, 2017

AIM Photonics Presents Cutting-Edge Integrated Photonics Technology Developments to Packed House at OFC 2017, the Optical Networking and Communication Conference & Exhibition April 11th, 2017

Discoveries

Geoffrey Beach: Drawn to explore magnetism: Materials researcher is working on the magnetic memory of the future April 25th, 2017

Using light to propel water : With new method, MIT engineers can control and separate fluids on a surface using only visible light April 25th, 2017

Graphene holds up under high pressure: Used in filtration membranes, ultrathin material could help make desalination more productive April 24th, 2017

Nanoparticle vaccine shows potential as immunotherapy to fight multiple cancer types April 24th, 2017

Announcements

Geoffrey Beach: Drawn to explore magnetism: Materials researcher is working on the magnetic memory of the future April 25th, 2017

Using light to propel water : With new method, MIT engineers can control and separate fluids on a surface using only visible light April 25th, 2017

Graphene holds up under high pressure: Used in filtration membranes, ultrathin material could help make desalination more productive April 24th, 2017

Nanoparticle vaccine shows potential as immunotherapy to fight multiple cancer types April 24th, 2017

Tools

Geoffrey Beach: Drawn to explore magnetism: Materials researcher is working on the magnetic memory of the future April 25th, 2017

NanoMONITOR shares its latest developments concerning the NanoMONITOR Software and the Monitoring stations April 21st, 2017

Nanomechanics, Inc. Unveils New Product at ICMCTF Show April 25th: Nanoindentation experts will launch the new Gemini that measures the interaction of two objects that are sliding across each other – not merely making contact April 21st, 2017

MSP Corporation Announces a New Breakthrough in Monodisperse Droplet Generation April 19th, 2017

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