Response to tilted magnetic fields in $Bi_2Sr_2CaCu_2O_8$ with columnar defects : Evidences for transverse Meissner effect


الملخص بالإنكليزية

The transverse Meissner effect (TME) in the highly layered superconductor $Bi_2Sr_2CaCu_2O_{8+y}$ with columnar defects is investigated by transport measurements. We present detailed evidence for the persistence of the Bose glass phase for $H_{perp}<H_{perp c}$ : (i) the variable-range vortex hopping process for low currents crosses over to the half-loops regime for high currents; (ii) in both regimes near $H_{perp c}$ the energy barriers vanish linearly with $H_{perp}$ ; (iii) the transition temperature is governed by $T_{BG}(H_{parallel},0) -T_{BG}(H_{parallel},H_{perp}) sim |H_{perp}| ^{1/ u_{perp}}$ with $ u_{perp}=1.0 pm 0.1$. Furthermore, above the transition as $H_{perp}to H_{perp c}^+$, moving kink chains consistent with a commensurate-incommensurate transition scenario are observed. These results thereby clearly show the existence of the TME for $H_{perp}<H_{perp c}$ .

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