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La violence de genre constitue l’un des crimes qui connaît une forte croissance et qui fait l’objet d’un intérêt certain pour la communauté scientifique. Le phénomène est complexe à analyser dans sa globalité car la plupart des auteurs commettent leurs crimes dans le foyer domestique. Étant donné le lien intrafamilial existant entre l’auteur et la victime, cette dernière reste dans le silence qui contribue à faire augmenter le « chiffre noir ». Par conséquent, l’analyse de ce phénomène, caché à cause de sa propre nature, montre ses limites. Des campagnes de sensibilisation à l’adoption de mesures législatives pour la prévention et répression de la violence, une connaissance approfondie de ce phénomène dans sa globalité est toutefois primordial pour le développement des politiques et des services d’aide aux victimes.Il faut souligner que les enquêtes et les recherches analysant ce comportement déviant et, depuis plusieurs décennies, proposées en permanence à des niveaux institutionnel et médiatique, ont tendance à considérer que la victime de la violence de genre ne peut être qu’une femme et que son auteur, un homme. Cette information, altérée dès le début, passe à travers des chaînes officielles (des médias aux campagnes de prévention) provoquant une sensibilisation unidirectionnelle qui relègue à l’état d’exceptions – qui souvent ne sont même pas prises en considération – les hypothèses que la violence puisse être subie et/ou perpêtrée aussi bien par les hommes que par les femmes. L’enquête présentée dans cet article a pour objectif de collecter des éléments d’évaluation encore inexistants en Italie. Ces données peuvent être utilisées pour vérifier s’il existe une réalité différente de celle qui n’est basée que sur les lieux communs et sur les préjudices et quelle serait sa dimension.Gender-based violence is a constantly increasing crime and continuously attracting a lot of interest in the scientific community. This is a complex phenomenon to analyse as a whole because perpetrators usually commit the acts of violence at home. For this reason, and also due to the intimate relationship between the author and the victim, this latter remains silent, so the dark number increases. Consequently, the analysis of this phenomenon, hidden just because of its nature, has its limits. A deep knowledge of this phenomenon as a whole, however, is important for the development of policies and services, for example sensibilisation campaigns and countermeasures to prevent and combat violence. It is important to point out that surveys and researches studying this deviant behaviour, and continuously proposed at an institutional level and disseminated by mass media, usually consider that the victim of gender-based violence is a woman and the perpetrator a man. This distorted information is transmitted through official channels (for example, mass media and sensibilisation campaigns) producing a consequent unidirectional sensibilisation which relegates as exceptions – often not taken into consideration – hypothesis that violence may be endured and/or committed by both sexes.The purpose of the survey presented in this article is to collect some evaluation data that do not exist yet in our country, data that will be useful in order to verify if it exists in reality, and if yes what extension it has, different from the one based exclusively on common sense and prejudices.

The various limits for the values of the shunt inductor and capacitor for highly hysteretic, tunnel-like Y[Ba.sub.2][Cu.sub.3][O.sub.7-[delta]] grain boundary Josephson junction is discussed.

The observations of macroscopic quantum tunneling and energy level quantization in Y[Ba.sub.2][Cu.sub.3][O.sub.7]-[delta] (YBCO)-based grain boundary (GB) biepitaxial Josephson junctions which could help to understand the mechanism involved in transport across grain boundaries is reported.

The presence of spontaneous currents in unconventional Josephson junction gives rise to the possibility of zero magnetic field magnetization states in an unconventional loop as qubit states in a Josephson quantum computing device. It is stated that using advanced fabrication techniques, Josephson junction arrays made of superconducting unconventional loops can be built.

Research describing the dynamical states of two dimensional Josephson arrays is presented. In particular the magnetic field response of arrays is investigated using equations with full inductance matrix.

Coherent passage of Cooper pairs in a Josephson junction (JJ) above the liquid nitrogen temperature has been the first impressive revolutionary effect induced by high critical temperature superconductors (HTS) in the domain of the study of Josephson effect (JE). But this has been only the start. A d-wave order parameter has lead to significant novel insights in the physics of the JE turning into a device the notion of a π-junction. Spontaneous currents in a frustrated geometry, Andreev bound states, long-range proximity effect have rapidly become standard terms in the study of the JE, standing as a reference bench for conventional systems based on low critical temperature superconductors (LTS) and inspiring analogies for junctions based on novel superconductors discovered in the meantime. The extreme richness of the physics of HTS JJs has not been adequately supported by the expected impact in the applications, the main reason lying in the complexity of these materials and in the consequent unsatisfactory yield and reproducibility of the performances of the JJs within the required limits. The continuous progress in material science, and specifically in the realization of oxide multi-layers, and in nanotechnologies applied to superconductors, accompanied by the advances in a better understanding of the properties of HTS and of HTS devices, has as a matter of fact opened possible novel scenarios and interest in the field. We intend to give a brief overview on interesting new problems concerning HTS JJs of inspiration also for other systems. We also review some ideas and experimental techniques on macroscopic quantum decay phenomena occurring in Josephson structures. The attention is mainly addressed to intermediate levels of dissipation, which characterize a large majority of low critical current Josephson devices and are therefore an unavoidable consequence of nanotechnology applied more and more to Josephson devices. [ABSTRACT FROM AUTHOR]

By means of numerical simulations we study the dynamics of the phase difference in faceted long Josephson junctions. We compare our simulations with experiments on a sample of high quality high-Tc biepitaxial junctions. Adjusting junction length and dissipation to reproduce the observed data we found a significant agreement, which permits to identify the observed resonances mostly as Eck steps. Some considerations are also made on the requirements to observe flux-flow or Fiske resonances in these junctions. [ABSTRACT FROM AUTHOR]

We have measured the energy level separation from the ground state to the first excited state in a high critical temperature superconductor d-wave Josephson junction. We observe that the bias current dependence of the energy level separation is strongly affected by the large shunt capacitance and inductance of the junction electrodes. In order to describe the effect of a shunt capacitance and shunt inductance on the junction dynamics we derive the equation of motion of the total system. In general such a circuit displays two resonance frequencies corresponding to two different energy scales. We discuss various limits for the values of the shunt inductor and capacitor. [ABSTRACT FROM AUTHOR]

We report on the latest developments in the study of transport properties of YBa2Cu3O7-δ (YBCO)-based grain boundary (GB) biepitaxial Josephson junctions. We have successfully extended the fabrication process, originally developed for (110) oriented SrTiO3 substrates, to (110) oriented LaA1O3 substrates in view of microwave applications. We will report, also, on the observation of conductance fluctuations, we believe related to the coherent diffusion of quasi-particles across the GB. These results, together with the recent observation of macroscopic quantum tunneling and energy level quantization in these junctions, could help cast some light on the mechanism involved in transport across grain boundaries and in revising the role and the effect of quasi particles in d-wave transport. [ABSTRACT FROM AUTHOR]

High quality epitaxial NbN/MgO/NbN Josephson junctions have been realized with MgO barriers up to a thickness of d = 1 nm. The junction properties coherently scale with the size of barrier, and low critical current densities down to 3 A/cm2 have been achieved for larger barriers. In this limit, junctions exhibit macroscopic quantum phenomena for temperatures lower than 90 mK. Measurements and junction parameters support the notion of a possible use of these devices for multiphoton quantum experiments, taking advantage of the fast non equilibrium electron-phonon relaxation times of NbN. [ABSTRACT FROM AUTHOR]

We report on the occurrence of multiple hopping and retrapping of a Brownian particle in a tilted washboard potential. The escape dynamic has been studied experimentally by measuring the switching current distributions as a function of temperature in a moderately damped NbN/MgO/NbN Josephson junction. At low temperatures the second moment of the distribution increases in agreement with calculations based on Kramers thermal activation regime. After a turnover temperature T*, the shape of the distributions starts changing and width decreases with temperature. We analyze the data through fit of the switching probability and Monte Carlo simulations and we find a good agreement with a model based on a multiple retrapping process. [ABSTRACT FROM AUTHOR]

Dissipation encodes the interaction of a quantum system with the environment and regulates the activation regimes of a Brownian particle. We have engineered grain boundary biepitaxial YBaCuO junctions to drive a direct transition from a quantum activated running state to a phase diffusion regime. The crossover to the quantum regime is tuned by the magnetic field and dissipation is described by a fully consistent set of junction parameters. To unravel phase dynamics in moderately damped systems is of general interest for advances in the comprehension of retrapping phenomena and in view of quantum hybrid technology. [ABSTRACT FROM AUTHOR]

Many experiments on high-temperature superconductors have shown paramagnetic behavior when the sample is field cooled. The paramagnetism was attributed to a d-wave order parameter creating pi-junctions in the samples. However, the same effect was later discovered in traditional low-temperature superconductors and conventional Josephson-junction arrays which are s wave. By simulating both conventional and mixed pi/conventional Josephson-junction arrays we determine that differences exist which may be sufficient to clearly identify the presence of pi junctions. In particular, the pi junctions cause a symmetry breaking providing a measurable signature of their presence.