Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Stevens researchers pioneer novel technique to make plasmonic nanogap arrays

07.09.2011
In the quest to exploit unique properties at the nanoscale, scientists at Stevens Institute of Technology have developed a novel technique for creating uniform arrays of metallic nanostructures.

A team of faculty and students in the Department of Physics and Engineering Physics, led by Dr. Stefan Strauf, appropriated methods from holographic lithography to demonstrate a new approach for scaling up the fabrication of plasmonic nanogap arrays while simultaneously reducing costs and infrastructure. A paper on the technique recently appeared in Nano Letters 11, 2715 (2011).

"Prof. Strauf is doing research at the forefront of physics," says Dr. Rainer Martini, Department Director for Physics and Engineering Physics. "His lab is producing research breakthroughs with impact well beyond his own field as well as providing excellent learning and publishing opportunities for graduate and undergraduate students."

Plasmonic nanogap arrays are essentially uniformly placed metallic nanostructures which feature a tiny air gap between neighbors. By creating strongly confined electrical fields under optical illumination, these tiny air gaps allow scientists to use the arrays in a variety of applications, particularly in the miniaturization of photonic circuits and ultrasensitive sensing. Such sensors could be used to detect the presence of specific proteins or chemicals down to the level of single molecules, or employed in high-resolution microscopy. Nanophotonic circuits, able to transmit huge amounts of information, are considered crucial to bring about the exaflop processing era and a new generation in computing power.

Established fabrication techniques for nanogap arrays have focused on serial methods, which are time-consuming, have a low throughput, and are consequently expensive. Holographic lithography (HL), an optical approach that takes advantage of interference patterns of laser beams to create periodic patterns, had been previously demonstrated to create sub wavelength features. Dr. Strauf's team advanced the HL methodology by using four-beam interference and the concept of a compound lattice to create tunable twin motive shapes into a polymer template, resulting in metallic air gaps down to 7 nm, seventy times smaller than the wavelengths of the blue laser light utilized to write the features.

The Stevens scientists extended the utility of HL to create gaps with results comparable to laborious serial fabrication techniques such as electron beam lithography or focused ion beam milling. Besides being a simpler and more cost-effective production method, their technique does not require a clean room and currently achieves 90% uniformity in the array pattern. Therefore, these innovations provide the foundation for making high-quality, large-scale arrays at a greater speed and lower cost than previously realizable.

"This research project provided me with an opportunity to become an expert with the HL technique," says Xi Zhang, the first author of the Nano Letters article and a PhD candidate. Xi and her fellow students are now measuring the surface enhanced Raman scattering (SERS) effects that result from these arrays and continue to improve the uniformity of the arrays during fabrication. "We just got some excellent results from first SERS experiment, and certainly there are more papers to follow up," she says.

Dr. Strauf is Director of the NanoPhotonics Laboratory (NPL) at Stevens, where he oversees cutting-edge research in the fields of solid-state nanophotonics and nanoelectronics. Research at the lab includes the development of fabrication methods for nanoscale materials and quantum device applications. Recent NPL projects have resulted in papers published on quantum dots and graphene. The lab has received project funding from the Air Force Office of Scientific Research and two National Science Foundation instrumentation grants. Dr. Strauf is also the recipient of the prestigious NSF CAREER Award.

About the Department of Physics and Engineering Physics

The mission of the Department of Physics and Engineering Physics at Stevens Institute of Technology is to provide a world-class scientific research and academic environment that fosters creation of new knowledge while educating and inspiring students at all levels as well as motivating faculty and support staff, to acquire, use, and advance the competencies needed to lead in scientific discovery and in the creation, application and management of technology to solve complex problems, invent new processes and products, and build new enterprises. The program has a strong focus on interdisciplinary projects and effectively combines classroom instruction with hands-on experience in state-of-the-art research laboratories. The Department has broad research programs, with special emphasis on the fields of atomic, molecular, and optical physics (AMO), photonics technology, quantum optics, and quantum information science. Learn more: www.stevens.edu/ses/physics

Christine del Rosario | EurekAlert!
Further information:
http://www.stevens.edu/ses/physics

More articles from Physics and Astronomy:

nachricht Climate cycles may explain how running water carved Mars' surface features
02.12.2016 | Penn State

nachricht What do Netflix, Google and planetary systems have in common?
02.12.2016 | University of Toronto

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: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

Im Focus: Fraunhofer ISE Develops Highly Compact, High Frequency DC/DC Converter for Aviation

The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

UTSA study describes new minimally invasive device to treat cancer and other illnesses

02.12.2016 | Medical Engineering

Plasma-zapping process could yield trans fat-free soybean oil product

02.12.2016 | Agricultural and Forestry Science

What do Netflix, Google and planetary systems have in common?

02.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>