64 research outputs found
TAUBERIAN THEOREM FOR THE OISTRIBUTIONAL STIELTJES TRANSFORMATION
ABSTRACT. In this paper we use the notion of L-quasiasymptotic at infinity of distributions to obtain a final value Tauberian theorem for the distributional Stieltje
Decay of the metastable phase in d=1 and d=2 Ising models
We calculate perturbatively the tunneling decay rate of the
metastable phase in the quantum d=1 Ising model in a skew magnetic field near
the coexistence line at T=0. It is shown that
oscillates in the magnetic field due to discreteness of the excitation
energy spectrum. After mapping of the obtained results onto the extreme
anisotropic d=2 Ising model at , we verify in the latter model the
droplet theory predictions for the free energy analytically continued to the
metastable phase. We find also evidence for the discrete-lattice corrections in
this metastable phase free energy.Comment: 4 pages, REVTe
Quantum transport through mesoscopic disordered interfaces, junctions, and multilayers
The study explores perpendicular transport through macroscopically
inhomogeneous three-dimensional disordered conductors using mesoscopic methods
(real-space Green function technique in a two-probe measuring geometry). The
nanoscale samples (containing atoms) are modeled by a tight-binding
Hamiltonian on a simple cubic lattice where disorder is introduced in the
on-site potential energy. I compute the transport properties of: disordered
metallic junctions formed by concatenating two homogenous samples with
different kinds of microscopic disorder, a single strongly disordered
interface, and multilayers composed of such interfaces and homogeneous layers
characterized by different strength of the same type of microscopic disorder.
This allows us to: contrast resistor model (semiclassical) approach with fully
quantum description of dirty mesoscopic multilayers; study the transmission
properties of dirty interfaces (where Schep-Bauer distribution of transmission
eigenvalues is confirmed for single interface, as well as for the stack of such
interfaces that is thinner than the localization length); and elucidate the
effect of coupling to ideal leads (``measuring apparatus'') on the conductance
of both bulk conductors and dirty interfaces When multilayer contains a
ballistic layer in between two interfaces, its disorder-averaged conductance
oscillates as a function of Fermi energy. I also address some fundamental
issues in quantum transport theory--the relationship between Kubo formula in
exact state representation and ``mesoscopic Kubo formula'' (which gives the
zero-temperature conductance of a finite-size sample attached to two
semi-infinite ideal leads) is thoroughly reexamined by comparing their answers
for both the junctions and homogeneous samples.Comment: 18 pages, 17 embedded EPS figure
From shallow to very shallow image of the highly active Kefalonia - Zakynthos fault system
4 pages, 2 figuresIn May 2022 and June 2023 two oceanographic cruises were carried out around the Ionian Islands with the aim of defining the real geometry of the strike-slip fault system of Kefalonia and of the reverse faults present south of Zakynthos. The acquired multidisciplinary and multiresolution data will also allow to understand the dynamics of the area offshore the Peoloponnese peninsula, the deformation of the surface sediments at the transition of the two systems, i.e. from reverse fault system to strike-slip fault system, and the relationship between the recorded seismicity and mapped fault activity. To date, the analysis of the processed data has allowed us to define the tectonic and morphological complexity of the fault system affecting the investigated area. [...]Thanks to the CNR for supporting the cruise with time ship, IONIANS 2022 project. Interpretation of seismic profile has been done using the Kindgom IHS Markit. Poseidon project has been supported by Eurofleet+ SEA02_13_POSEIDONPeer reviewe
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