Does a Bose-Glass State Exist in Commercial High-T$_c$ Wires?

The hypothesis that the vortex lattice induced by perpendicular magnetic field in films of PLD-YBCO is in a thermodynamic Bose glass state accounts for the inverse-square-root power law shown by the critical current density versus perpendicuar magnetic field.$^0$ We study here how robust such a state is to the addition of point pinning centers. This is done by first calculating the tilt modulus of the ``pristine'' Bose-glass state. It is found to diverge at long-wavelength along the magnetic-field/correlated-defect direction. A Larkin-Ovchinnikov analysis then yields a 2D/3D phase transition in collective pinning that is first-order. In particular, a {\it broken} Bose glass state characterized by finite Larkin domains, within which correlated pinning centers remain effective, exists at strong enough point pinning, at small enough coherence lengths. A signature of the broken glass state is found in the dependence shown by the critical current with film thickness along the c axis, which is predicted to crossover from [1] 2D to 3D collective-pinning behavior at a film thickness equal to the longitudinal Larkin scale $L_c$. \newline [1] J. Rodriguez \& M. Maley, Phys. Rev. B {\bf 73}, 094502 (2006).