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تسجيل مستخدم جديدTransition from a mixed to a pure d-wave symmetry in superconducting optimally doped YBa$_2$Cu$_3$O$_{7-x}$ thin films under applied fields
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We have probed the Landau levels of nodal quasi-particles by tunneling along a nodal direction of (110) oriented YBa$_2$Cu$_3$O$_{7-x}$ thin films with a magnetic field applied perpendicular to the $CuO_2$ planes, and parallel to the films surface. In optimally doped films and at low temperature, finite energy nodal states are clearly observed in films thinner than the London penetration depth. Above a well defined temperature the order parameter reverts to a pure emph{d}-wave symmetry.
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