Diffusive and ballistic motion in superconducting hybrid structures

Ballistic versus diffusive transport in graphene

Mario F. Borunda,1,2,* H. Hennig,2 and Eric J. Heller2,3 1Department of Physics, Oklahoma State University, Stillwater, Oklahoma 74078, USA 2Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA 3Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA (Received 9 April 2013; revised manuscript received 9 August 2013; publish...

Diffusive-ballistic crossover in 1D quantum walks.

We show that particle transport, as characterized by the equilibrium mean square displacement, in a uniform, quantum multibaker map, is generically ballistic in the long time limit, for any fixed value of Planck's constant. However, for fixed times, the semiclassical limit leads to diffusion. Random matrix theory provides explicit analytical predictions for the mean square displacement of a par...

Ballistic and Diffusive Thermal Conductivity of Graphene

Ballistic and diffusive transport of energy and heat in metals

We exploit a recently developed formalism to study the temporal behavior of the energy and heat transport in metals. This formalism shows the transition between ballistic and diffusive regimes and it highlights some interesting effects such as oscillations in the energy transport at very short-time scales. The energy relaxation of the conduction-band electrons in metals is considered to be gove...

Direct observation of the full transition from ballistic to diffusive Brownian motion in a liquid

At timescales once deemed immeasurably small by Einstein, the random movement of Brownian particles in a liquid is expected to be replaced by ballistic motion. So far, an experimental verification of this prediction has been out of reach due to a lack of instrumentation fast and precise enough to capture this motion. Here we report the observation of the Brownian motion of a single particle in ...