Diffusive-Ballistic Crossover in 1D Quantum Walks
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 …