Quantum transport through ballistic cavities: soft vs hard quantum chaos
We study transport through a two-dimensional billiard attached to two infinite leads by numerically calculating the Landauer conductance and the Wigner time delay. In the generic case of a mixed phase space we find a power-law distribution of resonance widths and a power-law dependence of conductance increments apparently reflecting the classical dwell time exponent, in striking difference to the case of a fully chaotic phase space. Surprisingly, these power laws appear on energy scales below the mean level spacing, in contrast to semiclassical expectations.
Huckestein
B
Institut fur Theoretische Physik, Universitat zu Koln, D-50937 Koln, Germany.
Ketzmerick
R
Lewenkopf
CH