Research Cover Story in Applied Physics Letters

2/23/2011

An article by Stevens Institute of Technology researchers featured as the cover page of Applied Physics Letters Volume 98, Issue 7 represents a step forward in techniques for the arrangement of nanowires.

Professors Dr. Chang-Hwan Choi and Dr. Eui-Hyeok (EH) Yang, and graduate students Wei Xu, Rajesh Leeladhar, and Yao-Tsan Tsai, focuses on nanowires, structures that are mere nanometers in diameter but have enormous potential in nanotechnology to create tiny circuits that would make possible nanoelectronics, nanophotonics, and nanobiotechnology. Such devices could forever change the way we harness energy, communicate, and treat disease.

"This highly promising research can lead to the development of reliable nano-actuators which in turn stand to benefit fields and applications as diverse as biomaterials, nano robots, artificial muscles, and high frequency nano antenna applications and is an affirmation of the cutting edge research that is taking place in the Micro/Nano Devices Laboratory," says Dr. Constantin Chassapis, Deputy Dean of the Charles V. Schaefer, Jr. School of Engineering and Science and Department Director of Mechanical Engineering.

The precise arrangement of nanowires on a large scale is crucial for any practical application. However, many current techniques for the controllable arrangement of nanowires suffer limitations.

The article, entitled, "Evaporative self-assembly of nanowires on superhydrophobic surfaces of nanotip latching surfaces," reports a technique that is highly effective in assembling nanowires. A colloid droplet of nanowires (i.e., nanowires dispersed in a water droplet) is placed on a nano-engineered superhydrophobic surface. As the droplet evaporates, two forces cause the nanowires to self-assemble on the specially-designed surface: hydrodynamic forces inside the droplet and capillary forces of the receding contact line of the droplet. Simple and convenient, the new self-assembly technique offers a high yield rate, improving the controlled arrangement of nanowires which may be used in nanodevices.

Dr. Chang-Hwan Choi
Dr. Chang-Hwan ChoiDr. Choi is an Assistant Professor of Mechanical Engineering at Stevens, and director of the Nano and Microfluidics Laboratory. His research focuses on developing simple and efficient methods of nanofabrication that display superior pattern regularity, size, and shape over a large area. Such research improves upon standard lithography methods, which do not cover an area large enough to successfully employ not only electronic but also non-electronic applications. Dr. Choi was honored with the prestigious 2010 Young Investigator Program (YIP) Award from the Office of Naval Research (ONR). He is also the recipient of a National Science Foundation (NSF) Fellowship.

Dr. EH Yang
Dr. EH Yang Dr. Yang is an Associate Professor of Mechanical Engineering at Stevens, as well as director of the Nanoelectronics Laboratory and multi-user Micro Device Laboratory. Dr. Yang’s research focuses on utilizing engineered low-dimensional carbon materials and nanostructures for realizing nanosensors/actuators and nanoelectronics/optoelecdtronnics devices. He has published a number of articles, including recent articles in Nano Letters, Langmuir, and Applied Physics Letters. Recently he secured an NSF grant to acquire a Nanoimprint Lithography System for Stevens Micro Device Lab.

About the Department of Mechanical Engineering
The Department of Mechanical Engineering confidently addresses the challenges facing engineering now and into the future, yet remains true to the vision of the founders of Stevens Institute in 1870 as one of the first engineering schools in the nation. The department mission is to produce graduates with a broad-based foundation in fundamental engineering principles and liberal arts together with the depth of disciplinary knowledge needed to succeed in a career in mechanical engineering or a related field, including a wide variety of advanced technological and management careers. This is accomplished through a broad-based Core Curriculum of applied sciences, engineering sciences, design, management, and the humanities, coupled with a long-standing honor system. Learn more: visit http://www.stevens.edu/ses/me

Visit the Nanotechnology Graduate Program to learn more about studying nanotechnology at Stevens: http://www.stevens.edu/nano/