At any given time, my group and I are involved in research on a variety of subjects in condensed matter physics. Because of the breadth of this field, it is important to expose graduate students and postdoctoral researchers to a wide spectrum of problems. A broad view is also important because new breakthroughs occur in different subareas of this field. Since the research projects are chosen because of their inherent scientific importance, we are sometimes working directly with experimentalists and at other times developing new formalisms and techniques to understand or solve a problem. We are often trying to predict the existence of new materials and attempting to explain or predict new properties of condensed matter systems.
Some of our current research is in the area of nanoscience and nanotechnology. The major systems under investigation are nanotubes, graphene, large molecules like C36, nanocrystals or quantum dots, clusters, onions, cones, horns, nanowires, etc. The quantum nature of these systems makes them physically interesting and provides a variety of possible applications.
There is almost always some work going on in my group on superconductivity, semiconductors, and predicting new materials. Currently, we are focused on increasing the superconducting transition temperature, photovoltaics, and new high pressure structures.
The selected publications in the next section are not meant to be representative (See list on Web.) but rather an example of recent papers.
H.K. Lee, M.L. Cohen, and S.G. Louie, “Selective functionalization of halogens on zigzag graphene nanoribbons: A route to the separation of zigzag graphene nanoribbons,” Appl. Phys. Letters 97, 233101 (2010).
F. Giustino, S.G. Louie, and M.L. Cohen, “Electron-phonon renormalization of the direct band gap of diamond,” Phys. Rev. Lett. 105, 265501 (2010).
M.L. Cohen, “Electron-phonon induced pairing and its limits for superconducting systems,” Physica E 43, 657 (2011).
V.W. Brar, R. Decker, H.-M. Solowan, Y. Wang, L. Maserati, K.T. Chan, H. Lee, C.O. Girit, A Zettl, S.G. Louie, M.L. Cohen, and M.F. Crommie,” Gate-controlled ionization and screening of cobalt adatoms on a graphene surface,” Nature Physics 7, 43 (2011).
K.T. Chan, H.K. Lee, and M.L. Cohen, “Gated adatoms on graphene studied from first principles,” Phys. Rev. B 83, 035405 (2011).
J. Noffsinger and M.L. Cohen, “Superconductivity in monolayer Pb on Si (111) from first principles,” Solid State Comm. 151, 421 (2011).
J.J. Crochet, J.D. Sau, J.G. Duque, S.K. Doorn, and M.L. Cohen, "Electrodynamic and excitonic intertube interactions in semiconducting carbon nanotube aggregates," ACS Nano 5, 2611 (2011).
J. Noffsinger and M.L. Cohen, “Electron-phonon coupling and superconductivity in double-walled carbon nanotubes,” Phys. Rev B 83, 165420 (2011).