  We use gauge-gravity duality to study the transport properties of a finite
density of charge carriers in a strongly-coupled theory with non-relativistic
symmetry. The field theory is N=4 supersymmetric SU(Nc) Yang-Mills theory in
the limit of large Nc and with large 't Hooft coupling, deformed by an
irrelevant operator, coupled to a number Nf of massive N=2 supersymmetric
hypermultiplets in the fundamental representation of the gauge group, i.e.
flavor fields. The irrelevant deformation breaks the relativistic conformal
group down to the Schroedinger group, which has non-relativistic scale
invariance with dynamical exponent z=2. Introducing a finite baryon number
density of the flavor fields provides us with charge carriers. We compute the
associated DC and AC conductivities using the dual gravitational description of
probe D7-branes in an asymptotically Schroedinger spacetime. We generically
find that in the infrared the conductivity exhibits scaling with temperature or
frequency that is relativistic, while in the ultraviolet the scalings appear to
be non-relativistic with dynamical exponent z=2, as expected in the presence of
the irrelevant deformation.
