Support UVa's Physics Department! >>
Click here for a printable version of this page.

Condensed Matter Seminars

ics Condensed Matter
Thursday, March 25, 2010
4:00 PM
Physics Building, Room 204
Note special time.
Note special room.
Gareth Alexander [Host: Andrew James]
University of Pennsylvania
"Symmetry breaking in smectics and surface models of their singularities"
 Slideshow (PDF)
The homotopy theory of topological defects in ordered media fails to completely characterize systems with broken translational symmetry. We argue that the problem can be understood in terms of the lack of rotational Goldstone modes in such systems and provide an alternate approach that correctly accounts for the interaction between translations and rotations. Dislocations are associated, as usual, with branch points in a phase field, whereas disclinations arise as critical points and singularities in the phase field. We introduce a three-dimensional model for two-dimensional smectics that clarifies the topology of disclinations and geometrically captures known results without the need to add compatibility conditions. Our work suggests natural generalizations of the two-dimensional smectic theory to higher dimensions and to crystals.

To add a speaker, send an email to phys-speakers@Virginia.EDU. Please include the seminar type (e.g. Condensed Matter Seminars), date, name of the speaker, title of talk, and an abstract (if available).