8th Liquid Matter Conference September 6-10, 2011 Wien, Austria ...

P5.72Wed 711:10-14:00Frictional response of colloidal crystals subject toquasicrystalline substrate potentialsJaffar Hasnain 11 Universität Wien, Himmelstrasse 43b/32, 1190, Vienna, AustriaQuasicrystals are of particular interest because of their atypically frictional, electronic, diffusive,and elastic properties as compared to their periodic counterparts [1, 2]. Here we report on computersimulations carried out to study the frictional response of a periodic two-dimensional colloidalcrystal subject to a quasicrystalline substrate potential. Using overdamped Langevin dynamics,we compare the results obtained for the quasicrystalline and crystalline substrates with variousdegrees of commensurability in order to shed light on the mechanism underlying the peculiarfrictional behavior of quasi-crystals. Our simulations are in good qualitative agreement with theexperimental results obtained by Bechinger and collaborators [3, 4].[1] D. P. DiVincenzo and P. J. Steinhardt. Quasicrytals The State of the Art. World Scientific,Singapore, second edition, 1999.[2] J. Y. Park, D. F. Ogletree, M. Salmeron, R. A. Ribeiro, P. C. Canfeld, C. J. Jenks, and P. A.Thiel. Science 309, 1354 (2005).[3] J. Mikhael, J. Roth, L. Helden, and C. Bechinger. Nature 454, 501 (2008). [4] J. Mikhael, M.Schmiedeberg, S. Rausch, J. Roth, H. Stark, and C. Bechinger. Proc. Natl. Acad. Sci. USA 107,7214 (2010).72