In this talk, I will present the existence of Large Deviation
Principles in the scope of fermionic systems at equilibrium. The
physical motivations beyond these studies are experimental measures of
electric resistance of nanowires in silicon doped with phosphorus
atoms. The latter demonstrates that quantum effects on charge
transport almost disappear for nanowires of lengths larger than a few
nanometers, even at a very low temperature (4.2 K). This presentation
is closely related to proving (mathematically speaking) for
interacting fermions (in presence of impurities) at equilibrium these
experimental results.
In the first part, I will describe the existence of a Large Deviation
Principle for free fermion systems subjected to external electric
fields. After that, I will state that for weakly interacting fermions
on the lattice, the logarithm moment generating function of
probability distributions associated with KMS states can be written as
the limit of logarithms of Gaussian Berezin integrals. The covariances
of the Gaussian integrals are shown to have a uniform determinant
bound and to be summable even in the disorder setting. Finally, I will
discuss how to prove a Large Deviation Principle for current
observables in the interacting setting.
Based on joint works with J. B. Bru and W. de Siqueira Pedra.