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Dynamics of driven vortex-antivortex matter in superconducting films with a magnetic dipole array

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 نشر من قبل Clessio Lima Leao
 تاريخ النشر 2008
  مجال البحث فيزياء
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We investigate theoretically vortex-antivortex (v-av) matter moving in thin superconducting films with a regular array of in-plane magnetic dipoles. Our model considers v-av pair creation induced by the local current density generated by the magnetic texture and the transport current and simulates the dynamics of vortices and antivortices by numerical integration of the Langevin equation of motion. Calculations of the transport properties at zero applied field show a strong dependence of the v-av dynamics on the current intensity and direction. The dynamics of the v-av matter is characterized by a series of creation and annihilation processes, which reflect on the time dependence of the electrical field, and by guided motion, resulting in a zero-field transverse resistance.

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