Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > Chemical Sensor on a Chip

The light is emitted by the laser (top), transported on the plasmonic waveguide (blue) and hits the detector (bottom right). How much of it is absorbed depends on the chemical composition of the liquid.
The light is emitted by the laser (top), transported on the plasmonic waveguide (blue) and hits the detector (bottom right). How much of it is absorbed depends on the chemical composition of the liquid.

Abstract:
They are invisible, but perfectly suited for analysing liquids and gases; infrared laser beams are absorbed differently by different molecules. This effect can for instance be used to measure the oxygen concentration in blood. At the Vienna University of Technology, this technique has now been miniaturized and implemented in the prototype for a new kind of sensor.

Chemical Sensor on a Chip

Vienna, Austria | Posted on June 12th, 2014

Specially designed quantum cascade lasers and light detectors are created by the same production process. The gap between laser and detector is only 50 micrometres. It is bridged by a plasmonic waveguide made of gold and silicon nitride. This new approach allows for the simple and cheap production of tiny sensors for many different applications.

Laser and Detector

Simple solid-state lasers, such as the well-known red ruby laser, consist of only one material. Quantum cascade lasers, on the other hand, are made of a perfectly optimized layer system of different materials. That way, the properties such as the wavelength of the laser can be tuned. When a voltage is applied to the layer structure, the laser starts to emit light. But the structure can also work the other way around; when it is irradiated with light, an electric signal is created.

Now a method has been developed to create a laser and a detector at the same time, on one single chip, in such a way that the wavelength of the laser perfectly matches the wavelength to which the detector is sensitive. This bifunctional material was created atomic layer for atomic layer at the center for micro- and nanostructures at the Vienna University of Technology. "As both parts are created in one step, laser and detector do not have to be adjusted. They are already perfectly aligned", says Benedikt Schwarz.

Leading the Light to the Detector

In conventional systems, the laser light has to be transmitted to the detector using carefully placed lenses. Alternatively, optical fibres can be used, but they usually transport all the light inside, without letting it interact with the environment, and therefore they cannot be used as sensors.

In the new element created at the Vienna University of Technology, the optical connection between quantum cascade laser and detector works in a completely different way. It is a plasmonic waveguide, made of gold and silicon oxide. "The light interacts with the electrons in the metal in a very special way, so that the light is guided outside the gold surface", says Benedikt Schwarz. "That is why the light can be absorbed by the molecules on its way between laser and detector."

The sensor chip can be submerged in a liquid. By measuring the decrease of the detected light intensity due to the presence of light absorbing molecules, the composition of the liquid can be determined. The sensor was tested with a mixture of water and alcohol. The water concentration can be measured with an accuracy of 0.06%.

As the wavelength can be influenced by changing the design of the layered structure, this sensor concept can be applied to a wide variety of molecules such as carbohydrates or proteins, for many different applications in chemical, biological or medical analytics.
Published in "Nature Communications".

####

About Vienna University of Technology, TU Vienna
With its eight faculties - mathematics and geo-information, physics, technical chemistry, informatics, civil engineering, architecture and regional planning, mechanical engineering and business science, electrical engineering and information technology – the Vienna University of Technology covers the classic engineering disciplines.

The TU Vienna has a great pool of specialists who are acting in a wide range of different topics in research, teaching and as partners of the economy. More than 2000 scientists do their research and teaching at highly advanced and modern institutes – in summary about 70. Although fundamental research has priority at the TU Vienna applied research is also done. Moreover services are offered as high-tech problem solving and examination expertise for industry and economy. Innovation orientated companies are highly interested in co-operating with the Vienna University of Technology because of its high-tech and high-quality research and its openness for requests of the economy.

The Vienna University of Technology puts great emphasis on co-operation between its own institutes as well as with other universities. Therefore the TU Vienna participates in several European Union (EU) and other research programmes.

The aim of the university was and still is to belong to the best. The effort to reach this aim is also expressed in its mission statement: With the aim of providing technology for people, our mission is to develop scientific excellence and wide-ranging competence in our students.

For more information, please click here

Contacts:
Bettina Neunteufl
+43 (1) 58801 41025

Copyright © AlphaGalileo

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

Nano-supercapacitors for electric cars July 25th, 2014

New imaging agent provides better picture of the gut July 25th, 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

Scientists Test Nanoparticle "Alarm Clock" to Awaken Immune Systems Put to Sleep by Cancer July 25th, 2014

Nanomedicine

New imaging agent provides better picture of the gut July 25th, 2014

Scientists Test Nanoparticle "Alarm Clock" to Awaken Immune Systems Put to Sleep by Cancer July 25th, 2014

Researchers create vaccine for dust-mite allergies Main Page Content: Vaccine reduced lung inflammation to allergens in lab and animal tests July 22nd, 2014

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

Sensors

Compact Vibration Harvester Power Supply with Highest Efficiency Opens Door to “Fix-and-Forget” Sensor Nodes July 23rd, 2014

Nano-sized Chip "Sniffs Out" Explosives Far Better than Trained Dogs: TAU researcher's groundbreaking sensor detects miniscule concentrations of hazardous materials in the air July 23rd, 2014

Tiny laser sensor heightens bomb detection sensitivity July 19th, 2014

Iranian Scientists Use Nanosensors to Achieve Best Limit for Early Cancer Diagnosis July 19th, 2014

Discoveries

New imaging agent provides better picture of the gut July 25th, 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

Scientists Test Nanoparticle "Alarm Clock" to Awaken Immune Systems Put to Sleep by Cancer July 25th, 2014

Iranian Scientists Produce Transparent Nanocomposite Coatings with Longer Lifetime July 24th, 2014

Announcements

Nano-supercapacitors for electric cars July 25th, 2014

New imaging agent provides better picture of the gut July 25th, 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

Scientists Test Nanoparticle "Alarm Clock" to Awaken Immune Systems Put to Sleep by Cancer July 25th, 2014

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals

Silicene Labs Announces the Launch of 2D Materials Briefing Book™ and 2D Materials Road-Heat Map™: Contributors Include One of the World's Foremost 2D Materials Scientists July 25th, 2014

New imaging agent provides better picture of the gut July 25th, 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

Scientists Test Nanoparticle "Alarm Clock" to Awaken Immune Systems Put to Sleep by Cancer July 25th, 2014

Photonics/Optics/Lasers

NUS scientists use low cost technique to improve properties and functions of nanomaterials: By 'drawing' micropatterns on nanomaterials using a focused laser beam, scientists could modify properties of nanomaterials for effective applications in photonic and optoelectric applicat July 22nd, 2014

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

Tiny laser sensor heightens bomb detection sensitivity July 19th, 2014

Future Electronics May Depend on Lasers, Not Quartz July 17th, 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