Elastic systems with correlated disorder: Response to tilt and application to surface growth

We study elastic systems such as interfaces or lattices pinned by correlated quenched disorder considering two different types of correlations: generalized columnar disorder and quenched defects correlated as similar to x- a for large separation x. Using functional renormalization group methods, we obtain the critical exponents to two-loop order and calculate the response to a transverse field h. The correlated disorder violates the statistical tilt symmetry resulting in nonlinear response to a tilt. Elastic systems with columnar disorder exhibit a transverse Meissner effect: disorder generates the critical field h(c) below which there is no response to a tilt and above which the tilt angle behaves as v similar to (h- h(c))(phi) with a universal exponent phi < 1. This describes the destruction of a weak Bose glass in type- II superconductors with columnar disorder caused by tilt of the magnetic field. For isotropic long- range correlated disorder, the linear tilt modulus vanishes at small fields leading to a power- law response v similar to h phi with phi > 1. The obtained results are applied to the Kardar- Parisi- Zhang equation with temporally correlated noise.