title: Universality for moving stripes: a hydrodynamic theory of polar active smectics.
abstract: We present a theory of moving stripes ("polar active smectics"), both with and without number conservation. The latter is described by a compact anisotropic Kardar-Parisi-Zhang equation, which implies smectic order is quasilong ranged in d=2 and long ranged in d=3. In d=2 the smectic disorders via a Kosterlitz-Thouless transition, which can be driven by either increasing the noise or varying certain nonlinearities. For the number-conserving case, giant number fluctuations are greatly suppressed by the smectic order, which is long ranged in d=3. Nonlinear effects become important in d=2.
authors.affiliation: College of Science, The China University of Mining and Technology, Xuzhou Jiangsu 221116, People's Republic of China.
authors.forename: Leiming
authors.initials: L
authors.lastname: Chen
authors.forename: John
authors.initials: J
authors.lastname: Toner