Interference patterns for optical landscapes

A monolayer of colloidal particles exposed to interfering laser beams experience a periodic optical potential due to optical gradient forces. Because the number of beams, their angle of incidence and their intensity can be easily controlled, this allows the creation of artificial substrate potentials with tunable geometry and substrate strength. With this approach one can study structural phase transitions of monolayers on crystalline and quasicrystalline substrates.

Further information

Phase behavior of colloidal monolayers on quasiperiodic Substrates
Jules Mikhael, Günter Gera, Thomas Bohlein, and Clemens Bechinger
Soft Matter 7, 1352 (2011)
Archimedean-like colloidal tilings on substrates with decagonal and tetradecagonal symmetry
M. Schmiedeberg, J. Mikhael, S. Rausch, J. Roth, L. Helden, C. Bechinger, and H. Stark
Eur. Phys. J. E 32, 25 (2010)
Archimedean-like tiling on decagonal quasicrystalline surfaces
J. Mikhael, J. Roth, L. Helden, C. Bechinger
Nature 454, 501 (2008)
Tailoring of phononic band structures in colloidal crystals
J. Baumgartl, M. Zvyagolskaya, C. Bechinger
Phys. Rev. Lett. 99, 205503 (2007)
Colloids on patterned substrates
C. Bechinger, E. Frey
in Soft Matter, edited by G. Gompper, M. Schick (Wiley-VCH) 3, 87 (2007)
Strain-induced domain formation in two-dimensional colloidal systems
S. Bleil, H.H.v. Grünberg, J. Dobnikar, R. Castaneda-Priego, C. Bechinger
Europhys. Lett. 73, 450 (2006)
Locked-floating-solid to locked-smectic transition in colloidal systems
J. Baumgartl, M. Brunner, C. Bechinger
Phys. Rev. Lett. 93, 168301 (2004)