Fluctuations & Noise Lab

We study stochastic problems with direct relevance for the understanding of experimental data and for describing how nature actually works at the microscopic level. The properties of fluctuations are being used to describe the time evolution of a variety of dynamical systems. In particular, our focus is on:

COMPLEX SYSTEMS : Analytical tools are also being developed to account for the wide variety of phenomena which can be described within the framework of stochastic processes in terms of complex scaling phenomena. Stochastic phenomena occurring in real extended physical systems exhibit different degrees of correlation. The variance at large t scales as a power law, of the Hurst exponent H. H ranges from 0 to 1. The value H=0.5 corresponds to the ordinary uncorrelated Brownian motion, while H<0.5 and H>0.5 correspond respectively to anticorrelated and correlated signals. The analysis of the Hurst exponent is nowadays considered a practical instrument in fields as biophysics (DNA sequence, gait fluctuations), econophysics, cloud breaking and many others (read more).

DISORDERED MATERIALS and QUANTUM DEVICES : Transport and noise properties of low dimensional electronic systems, such as Quantum Well and Quantum Dot Heterostructures and Josephson Junction Arrays . This activity aims to the characterization of current fluctuations (in the dark and in the presence of monochromatic radiation) in new generation of detectors.

Critical phenomena that result from both quenched disorder and interaction in electronic systems (such as disordered inorganic and organic semiconductors and insulators, high-Tc superconductors). The research ultimately aims at investigating the basic physical processes underlying the functioning of devices based on disordered materials using current noise investigation. One debated point concerns the mechanism of charge transport and the role of traps (read more).