Abstract
We find a renormalized “time-dependent diffusion coefficient,” , for pulsed excitation of a nominally diffusive sample by solving the Bethe-Salpeter equation with recurrent scattering. We observe a crossover in dynamics in the transformation from a quasi-1D to a slab geometry implemented by varying the ratio of the radius, , to the length, , of the cylindrical sample with reflecting side walls and open ends. Immediately after the peak of the transmitted pulse, falls linearly with a nonuniversal slope that approaches an asymptotic value for . The value of extrapolated to depends only upon the dimensionless conductance for and only upon for , where is the wave vector and is the bare mean free path.
- Received 7 November 2003
DOI:https://doi.org/10.1103/PhysRevLett.92.173902
©2004 American Physical Society