Dr. Daniel Gunlycke, a research physicist in the Chemistry Division at the U.S. Naval Research Laboratory (NRL), is a recipient of the 2013 Young Investigator Award from the NRL Edison Chapter of the Sigma Xi scientific research society. Sigma Xi's Young Investigator Award recognizes scientists for outstanding research within 10 years of their highest earned degree and their ability to communicate their research to the public. Dr. Gunlycke is recognized for pioneering contributions to the understanding of the electronic properties of graphene nanostructures.
Dr. Gunlycke received his bachelor's degree from the University of Gothenburg and his master's degree from Chalmers University of Technology, both degrees in physics. He conducted his thesis research at Imperial College, London under the supervision of Professor Vlatko Vedral exploring quantum entanglement in Ising chains. He then went on to complete a doctorate in materials science at the University of Oxford under the supervision of Professor Andrew Briggs and Emeritus Professor David Pettifor. His dissertation work describes how quantum information could be processed in carbon nanotubes. Dr. Gunlycke was then awarded an NRC Research Associateship allowing him to work on electronic and transport properties of graphene nanoribbons with Dr. Carter White at NRL. Later, Dr. Gunlycke became a member of the permanent staff and has since been running and participating in many research programs with an emphasis on graphene and other two-dimensional crystals.
Dr. Gunlycke is well known for his research on the importance of edge effects on the electronic properties of graphene nanoribbons. Graphene gained a lot of attention around 2005, in part because of its potential to replace silicon and other semiconductors in nanoscale electronic devices. Hence, laboratories worldwide started to cut graphene into narrow ribbons using e-beam lithography, hoping to obtain carbon nanotube-like properties with suitable confinement-induced band gaps.
In a couple of seminal papers, Dr. Gunlycke and colleagues showed that the conductance in ribbons narrow enough to generate an acceptable band gap is severely degraded by edge roughness, which causes strong Anderson localization that ultimately turns the nanoribbons into insulators. Their findings, since confirmed by many other groups, have changed the direction of the field and led leading experimental groups to search for alternative methods of making nanoribbons with smooth edges, including chemical derivation, bottom-up synthesis, Joule heating, cutting graphene with nanoparticles, and unzipping of carbon nanotubes, explains Dr. Carter White, NRL's Senior Scientist for Theoretical Chemistry.
More recently, Dr. Gunlycke has explored the properties of an extended line defect observed and controllably fabricated in graphene. This line defect holds a lot of promise because it is well defined at the atomic level and could therefore be made reproducibly. Furthermore, Dr. Gunlycke has shown that the symmetry of this line defect leads to several properties that could be useful for future applications. In particular, he has established that it is semitransparent and behaves as a valley filter, which is a crucial component if researchers are to develop valley-based electronics. He has also found that two parallel, decorated line defects exhibit a transport gap that could be exploited in graphene resonant tunneling transistors.
Dr. Gunlycke's pioneering contributions to the understanding of graphene nanostructures are paving the way to future diverse applications for the Navy in areas ranging from ballistic electronic devices to anti-static coatings.