Hall Effect in the mixed state of moderately clean superconductors.pdfVIP

8 LETTER TO THE EDITOR 9 9 1 p Hall Effect in the mixed state of moderately clean e S superconductors 5 2 I Vekhter and A Houghton ] n Department of Physics, Brown University, Providence, RI 02912-1843, USA o c - Abstract. The Hall conductivity in the mixed state of a clean (l ≫ ξ ) type-II s-wave r 0 p superconductor is determined from a microscopic calculation within a quasiclassical u approximation. We find that below the superconducting transition the contribution s t. to the transverse conductivity due to dynamical fluctuations of the order parameter a m is compensated by the modification of the quasiparticle contribution. In this regime - the nonlinear behaviour of the Hall angle is governed by the change in the effective d quasiparticle scattering rate due to the reduction in the density of states at the Fermi n o level. The connection with experimental results is discussed. c [ 3 v PACS numbers: 74.25.Fy, 74.60.-w, 74.60.Ge 2 2 1 0 1 6 9 / t a m - d n o Short title: LETTER TO THE EDITOR c : v i February 1, 2008 X r a 2 The Hall effect in the mixed state of type-II superconductors has remained a theoretical puzzle for almost thirty years [1]. The existing phenomenological [2, 3] theories predict that the Hall angle in the flux-flow regime is either identical to that in the normal state [2] or constant [3]. Theories which make use of the time-dependent Ginzburg-Landau equations (TDGL) also find no modification of the Hall conductivity in the superconductin