Dynamics of fluctuations below a stationary bifurcation to electroconvection in the planar nematic liquid crystal N4.

نویسندگان

  • Xin-Liang Qiu
  • Guenter Ahlers
چکیده

We fitted C(k,tau,epsilon) proportional to exp([-sigma(k,epsilon)tau] to time-correlation functions C(k,tau,epsilon) of structure factors S(k,t,epsilon) of shadowgraph images of fluctuations below a supercritical bifurcation at V(0)=V(c) to electroconvection of a planar nematic liquid crystal in the presence of a voltage V=sqrt[2]V(0)cos((2pift) [k=(p,q) is the wave vector and epsilon identical with V(2)(0)/V(2)(c)-1]. There were stationary oblique (normal) rolls at small (large) f. Fits of a modified Swift-Hohenberg form to sigma(k,epsilon) gave f-dependent critical behavior for the minimum decay rates sigma(0)(epsilon) and the correlation lengths xi(p,q)(epsilon).

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عنوان ژورنال:
  • Physical review letters

دوره 94 8  شماره 

صفحات  -

تاریخ انتشار 2005