arXiv subjects

Luca Bonci

Publications and source records attributed to Luca Bonci.

3 recordsLinked to original sources

arXiv1999

Chaotic enhancement of decay. The effect of classical phase space structure

We investigate the decay process from a time dependent potential well in the semiclassical regime. The classical dynamics is chaotic and the decay rate shows an irregular behavior as a function of the system parameters. By studying the weak-chaos regime we are able to connect the decay irregularities to the presence of nonlinear resonances in the classical phase space. A quantitative analytical prediction which accounts for the numerical results is obtained.

chao-dyn↗

arXiv1999

The addition spectrum of interacting electrons: Parametric dependence

The addition spectrum of a disordered stadium is studied for up to 120 electrons using the self consistent Hartree-Fock approximation for different values of the dimensionless conductance and in the presence and absence of a neutralizing background. In all cases a Gaussian distribution of the addition spectrum is reached for $r_s \leq 1$. An empirical scaling for the distribution width in the presence of a neutralizing background is tested and seems to describe rather well its dependence on the dimensionless conductance.

cond-mat.mes-hall↗

arXiv1998

Tunneling rate fluctuations induced by non-linear resonances: a quantitative treatment based on semiclassical arguments

We investigate the tunneling process between two symmetric stable islands of a forced pendulum Hamiltonian in the weak chaos regime. We show that when the tunneling doublet is quantized over a classical non-linear resonance the tunneling rate strongly deviates from the semiclassical prediction. This mechanism is responsible for the irregular dependence of the tunneling rate on the system parameters. The weak-chaos condition allows us to make a theoretical prediction which agrees very well with the numerical results. This opens up a possible avenue to a general theory on the dependence of quantum tunneling on classical chaos.

chao-dyn↗