Prof. Joel Therrien from University of Massacusetts-Lowell will give a special seminar.

We would like to invite physics students to attend the seminar.

        < Information>

     1. Date and time : 2013/7/25(Thu) 11:00

     2. Place : 31355 Department of Physics seminar room ,Natural science 1

     3. Invited speaker : Prof. Joel Therrien (ECE Dept, University of Massachusetts-Lowell) 

     4. Title : Beyond Graphene: Synthesis of Single Layer Graphitic Carbon Nitride — A Carbon-Nitrogen Alloy System

     5. Abstract : Graphene attracted the world’s attention since its discovery in 2004. Dubbed “the next silicon” graphene has an impressive array of properties that made it a compelling potential competitor for silicon. However as time passed, the limitations in graphene have become more apparent and less likely to be overcome. In the meantime other 2-D materials have emerged. It is clear now that two-dimensional materials will exist as a unique class of materials. We have begun exploring a promising material: single layer graphitic carbon nitride (referred to as melon). The structure of melon resembles graphene with a hexagonal lattice of atoms, except that every other atom is either carbon or nitrogen. Due to nitrogen’s valency, the melon lattice has a lacey structure. Melon is a wide-bandgap semiconductor, with an optical bandgap of approximately 2.6eV. Ourgroup has succeeded in making melonat the wafer scale. Raman spectroscopy has been performed on single layer melon and multi layer samples.  Much like graphene, melon shows a unique raman spectrum when in single layer form. These experimental results have been compared to theoretical calculations for possible melon structures. Aside from Raman, a suite of materials characterization techniques has been applied to it to determine structural, electrical, and optical properties. Finally, results of the first melon based transistor will be discussed.