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

Ag/ZnO-Nanorods Schottky diodes based UV-PDs are fabricated and tested May 26th, 2017

New metamaterial-enhanced MRI technique tested on humans May 26th, 2017

Controlling 3-D behavior of biological cells using laser holographic techniques May 26th, 2017

Unveiling the quantum necklace: Researchers simulate quantum necklace-like structures in superfluids May 26th, 2017

Nanomechanics, Inc. to Exhibit at the SEM Conference: Nanoindentation experts will attend and exhibit their instruments at the Conference and Exposition on Experimental and Applied Mechanics in Indianapolis May 25th, 2017

Imaging

New metamaterial-enhanced MRI technique tested on humans May 26th, 2017

The brighter side of twisted polymers: Conjugated polymers designed with a twist produce tiny, brightly fluorescent particles with broad applications May 16th, 2017

UnitySC Announces Wafer Thinning Inspection System; Win from Power Semiconductor IDM for Automotive: Leading IDM Selects New 4See Series Automated Defect Inspection Platform for Power Semiconductor Automotive Applications May 11th, 2017

Three-dimensional Direction-dependent Force Measurement at the Subatomic Scale: International researchers led by Osaka University develop a microscopy technique to probe materials at the subatomic scale in multiple directions simultaneously May 11th, 2017

Chemistry

Stanford scientists use nanotechnology to boost the performance of key industrial catalyst May 18th, 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

New research helps to meet the challenges of nanotechnology: Research helps to make the most of nanoscale catalytic effects for nanotechnology January 20th, 2017

Ultra-precise chip-scale sensor detects unprecedentedly small changes at the nanoscale January 20th, 2017

New graphene-based system could help us see electrical signaling in heart and nerve cells: Berkeley-Stanford team creates a system to visualize faint electric fields December 19th, 2016

Govt.-Legislation/Regulation/Funding/Policy

New metamaterial-enhanced MRI technique tested on humans May 26th, 2017

Controlling 3-D behavior of biological cells using laser holographic techniques May 26th, 2017

Unveiling the quantum necklace: Researchers simulate quantum necklace-like structures in superfluids May 26th, 2017

Researchers find new way to control light with electric fields May 25th, 2017

Chip Technology

Researchers find new way to control light with electric fields May 25th, 2017

Nanometrics Announces Retirement Plans of CEO Timothy Stultz: Dr. Stultz to Continue as Director May 25th, 2017

GLOBALFOUNDRIES and Chengdu Partner to Expand FD-SOI Ecosystem in China: More than $100M investment to establish a center of excellence for FDXTM FD-SOI design May 23rd, 2017

Plasmon-powered upconversion nanocrystals for enhanced bioimaging and polarized emission: Plasmonic gold nanorods brighten lanthanide-doped upconversion superdots for improved multiphoton bioimaging contrast and enable polarization-selective nonlinear emissions for novel nanoscal May 19th, 2017

Discoveries

Ag/ZnO-Nanorods Schottky diodes based UV-PDs are fabricated and tested May 26th, 2017

New metamaterial-enhanced MRI technique tested on humans May 26th, 2017

Controlling 3-D behavior of biological cells using laser holographic techniques May 26th, 2017

Unveiling the quantum necklace: Researchers simulate quantum necklace-like structures in superfluids May 26th, 2017

Announcements

Ag/ZnO-Nanorods Schottky diodes based UV-PDs are fabricated and tested May 26th, 2017

New metamaterial-enhanced MRI technique tested on humans May 26th, 2017

Controlling 3-D behavior of biological cells using laser holographic techniques May 26th, 2017

Unveiling the quantum necklace: Researchers simulate quantum necklace-like structures in superfluids May 26th, 2017

Tools

New metamaterial-enhanced MRI technique tested on humans May 26th, 2017

Nanometrics Announces Retirement Plans of CEO Timothy Stultz: Dr. Stultz to Continue as Director May 25th, 2017

Nanomechanics, Inc. to Exhibit at the SEM Conference: Nanoindentation experts will attend and exhibit their instruments at the Conference and Exposition on Experimental and Applied Mechanics in Indianapolis May 25th, 2017

Plasmon-powered upconversion nanocrystals for enhanced bioimaging and polarized emission: Plasmonic gold nanorods brighten lanthanide-doped upconversion superdots for improved multiphoton bioimaging contrast and enable polarization-selective nonlinear emissions for novel nanoscal May 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