title: Transformation from walls to disclination lines: statics and dynamics of the pincement transition.
abstract: We present an experimental and theoretical study of the pincement phenomenon-transformation of a wall associated with the Fréedericksz transition into a pair of disclination lines. We measure the velocity of the boundary (front) between the two states as a function of the voltage. Experimental results are recovered by numerical simulations based on the nematic tensor order parameter, which also reveal the detailed three-dimensional structure of the front. By introducing reduced models we obtain approximate expressions for the two-state coexistence voltage and the front velocity. We find a bifurcation scenario incorporating a pair of saddle nodes at which the wall and disclination solutions appear or disappear.
authors.affiliation: Experimentalphysik V, Universität Bayreuth, D-95440 Bayreuth, Germany. alberto.delozar@uni-bayreuth.de
authors.forename: Alberto
authors.initials: A
authors.lastname: de Lózar
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Schöpf
authors.forename: Ingo
authors.initials: I
authors.lastname: Rehberg
authors.forename: Daniel
authors.initials: D
authors.lastname: Svensek
authors.forename: Lorenz
authors.initials: L
authors.lastname: Kramer