McGill.CA / Science / Department of Physics

CPM Seminar

Experimental test of a fluctuation-induced first-order phase transition

John Bechhoefer

Physics Department
Simon Fraser University

We report results on the first experiment to test quantitatively the Halperin-Lubensky-Ma (HLM) theory of fluctuation-induced first-order phase transitions. We measure the strength of the first-order discontinuity of the nematic--smectic-A (NA) transition in a liquid-crystal system as a function of applied magnetic field and also effective molecule length. In both cases, significant disagreement with HLM is observed. We tentatively ascribe this to the neglect of smectic fluctuations in the HLM theory.

Tuesday, May 11th 1999, 14:30
Ernest Rutherford Physics Building, Board room (104)