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Nonlinear MHD modeling of toroidal pinch configurations for hot plasma magnetic confinement describes several features of the helical self-organization process, which is observed in both reversed-field pinches and tokamaks. It can also give a hint on why transport barriers are formed, by far one of the more interesting observations in experiments. The work tackles these two topics, helical self-organization and transport barriers formation - adding further information and examples to the results already presented in [Veranda, et al, Nucl.Fus. 60 016007 (2020)]. Regarding the topic of helical self-organization, a synthesis of the results obtained by a 3D nonlinear viscoresistive magnetohydrodynamics model will be presented. Modelling predicts a technique to "channel" reversed-field pinches into a chosen macroscopic helical shape and also predicts that the features of such helical self-organization, studied in the RFX-mod experiment in Padova, depend on two parameters only: plasma dissipation coefficients and edge radial magnetic field. They can be exploited to calm the natural tendency of reversed-field pinches to a "sawtoothing" dynamics, i.e. by decreasing visco-resistive dissipation and using helical edge fields not resonating with the plasma safety factor. Regarding the MHD description of the process of formation of transport barriers by magnetic chaos healing, we will describe the computation of Lagrangian structures, hidden in the weakly stochastic behaviour of magnetic field lines, acting as barriers to the transport. The radial position of such structures is observed to correspond to higher gradients of magnetic field lines connection length to the edge: this provides a further indication of their possible role in the formation of electron temperature barriers. [ABSTRACT FROM AUTHOR]

In this study a multi-technique analysis was performed on the decorated surfaces of four ancient pottery fragments dated back XIX century A.D. withdrawn from the archaeological site of the medieval Agsu town, in Azerbaijan. During the last decade, the site underwent to an extensively archaeometric investigation by means of different non-destructive, or micro-destructive, techniques. In this work we focused our attention on the characterization of the pigmenting agents and glazes at different spatial scales from elemental to microscopic domain by using portable and not-portable equipments. In particular, the elemental and molecular compositions were successfully determined by X-ray fluorescence (XRF) and Raman spectroscopy, respectively. On one side, data deriving from portable instrument were compared with those previously obtained from not-portable approach, in view of future in situ investigations. On the other side, the overall obtained results appear crucial for the reconstruction of the production technology used by craftsman of the past. [ABSTRACT FROM AUTHOR]

The new strontium atomic clock at INRIM seeks to establish a new frontier in quantum measurement by joining state-of-the-art optical lattice clocks and the quantized electromagnetic field provided by a cavity QED setup. The goal of our experiment is to apply advanced quantum techniques to state-of-the-art optical lattice clocks, demonstrating enhanced sensitivity while preserving long coherence times and the highest accuracy. In this paper we describe the current status of the experiment and the prospected sensitivity gain for the designed cavity QED setup. [ABSTRACT FROM AUTHOR]

We investigate the interplay of voltage-driven excitations and electron-electron interactions in a pair of counterpropagating helical channels capacitively coupled to a time-dependent gate. By focusing on the non-equilibrium spectral properties of the system, we show how the spectral function is modified by external drives with different time profile in presence of Coulomb interactions. In particular, we focus on a Lorentzian drive and a square single pulse. In presence of strong enough electron-electron interactions, we find that both drives can result in minimal excitations, i.e. characterized by an excess spectral function with a definite sign. This is in contrast with what happens in the non-interacting case, where only properly quantized Lorentzian pulses are able to produce minimal excitations. [ABSTRACT FROM AUTHOR]

We work out the ground-state diagram of weakly-repulsive penetrable bosons, using mean-field theory with a Gaussian ansatz on the single-particle wave function. Upon compression, the fluid transforms into a cluster supersolid, whose structure is characterized for various choices of the embedding space. In Euclidean space, the stable crystals are those with the most compact structure, i.e., triangular and fcc in two and three dimensions, respectively. For particles confined in a spherical surface, as the sphere radius increases we observe a sequence of transitions between different cluster phases, all having a regular or semiregular polyhedron as supporting frame for the clusters. The present results are relevant for the behavior of ultracold bosons weakly coupled to a Rydberg state. [ABSTRACT FROM AUTHOR]

We describe a method for including van der Waals (vdW) interactions in Density Functional Theory (DFT) using the Maximally-Localized Wannier functions (MLWFs), which is free from empirical parameters. With respect to the previous DFT/vdW-WF2 version, in the present DFT/vdW-WF2-x approach, the empirical, short-range, damping function is replaced by an estimate of the Pauli exchange repulsion, also obtained by the MLWFs properties. Applications to systems contained in the popular S22 molecular database and to the case of adsorption of Ar on graphite, and Xe and water on graphene, indicate that the new method, besides being more physically founded, also leads to a systematic improvement in the description of systems where vdW interactions play a significant role. [ABSTRACT FROM AUTHOR]

Thanks to versatile optoelectronic properties solution processable perovskites have attracted increasing interest as active materials in photovoltaic and light emitting devices. However, the deposition of perovskite thin films necessitates wide range solvents that are incompatible with many other solution-processable media, including polymers that are usually dissolved by the perovskite solvents. In this work, we demonstrate that hybrid perovskite thin films can be coupled with all polymer planar photonic crystals with different approaches to achieve emission intensity enhancement and reshaping using different approaches. The possibility to control and modify the emission spectrum of a solution processable perovskite via a simple spun-cast polymer structure is indeed of great interest in optoelectronic applications requiring high color purity or emission directionality. Furthermore, thanks to the ease of fabrication and scalability of solution-processed photonic crystals, this approach could enable industrial scale production of low-cost, large area, lightweight and flexible polymer-perovskite lighting devices, which may be tuned without resorting to compositional engineering. [ABSTRACT FROM AUTHOR]

Physical and biological systems often exhibit intermittent dynamics with bursts or avalanches (active states) characterized by power-law size and duration distributions. These emergent features are typical of systems at the critical point of continuous phase transitions, and have led to the hypothesis that such systems may self-organize at criticality, i.e. without any fine tuning of parameters. Since the introduction of the Bak-Tang-Wiesenfeld (BTW) model, the paradigm of self-organized criticality (SOC) has been very fruitful for the analysis of emergent collective behaviors in a number of systems, including the brain. Although considerable effort has been devoted in identifying and modeling scaling features of burst and avalanche statistics, dynamical aspects related to the temporal organization of bursts remain often poorly understood or controversial. Of crucial importance to understand the mechanisms responsible for emergent behaviors is the relationship between active and quiet periods, and the nature of the correlations. Here we investigate the dynamics of active (θ-bursts) and quiet states (δ-bursts) in brain activity during the sleep-wake cycle. We show the duality of power-law (θ, active phase) and exponential-like (δ, quiescent phase) duration distributions, typical of SOC, jointly emerge with power-law temporal correlations and anti-correlated coupling between active and quiet states. Importantly, we demonstrate that such temporal organization shares important similarities with earthquake dynamics, and propose that specific power-law correlations and coupling between active and quiet states are distinctive characteristics of a class of systems with self-organization at criticality. [ABSTRACT FROM AUTHOR]

Recently the possibility to exploit quantum-mechanical effects to increase the performance of energy storage has raised a great interest. It consists of N two-level systems coupled to a single photonic mode in a cavity. We demonstrate the emergence of a quantum advantage in the charging power on this collective model (Dicke Quantum Battery) with respect to the one in which each two-level system is coupled to its own separate cavity mode (Rabi Quantum Battery). Moreover, we discuss the model of a Quantum Supercapacitor. This consists of two chains, one containing electrons and the other one holes, hosted by arrays of double quantum dots. The two chains are in close proximity and embedded in the same photonic cavity, in the same spirit of the Dicke model. We find the phase diagram of this model showing that, when transitioning from the ferro/antiferromagnetic to the superradiant phase, the quantum capacitance of the model is greatly enhanced. [ABSTRACT FROM AUTHOR]

The search for optimal receivers endowed with photon-number-resolving capability has led us to consider Silicon photomultipliers for Quantum Optics experiments. By adopting an optimization procedure in order to reduce the spurious effects characterizing these detectors, we succeeded in detecting nonclassical correlations between the two parties of mesoscopic twin-beam states and in obtaining subPoissonian conditional states. These results put SiPMs forward for the implementation of Quantum Information and Communication protocols. [ABSTRACT FROM AUTHOR]

The essential features of many interfaces driven out of equilibrium are described by the same equation—the Kardar-Parisi-Zhang (KPZ) equation. How do living interfaces, such as the cell membrane, fit into this picture? In an endeavour to answer such a question, we proposed in [F. Cagnetta, M. R. Evans, D. Marenduzzo, PRL 120, 258001 (2018)] an idealised model for the membrane of a moving cell. Here we discuss how the addition of simple ingredients inspired by the dynamics of the membrane of moving cells affects common kinetic roughening theories such as the KPZ and Edwards-Wilkinson equations. [ABSTRACT FROM AUTHOR]

The possibility to evaluate the molecular diffusivity in polymer thin films used for packaging and device encapsulation directly in-situ would represent a paradigm changer in the assesment of barrier properties and of air quality. Indeed, employing the packaging itself as a smart sensor could lead to waste reduction and mitigate food poisoning effects. In this work, we demonstrate a new technique that exploits simple UV-Vis reflectance spectroscopy to identify the kinetic of diffusion of small molecules in the vapor phase through polymer thin films and polymer multilayered structures. The new method allows then to assess the presence of the analyte in air and its diffusion coefficient in agreement with gravimetric data reported in literature. [ABSTRACT FROM AUTHOR]

The non-thermal mechanisms, underlying the damage induced on human cells by radiofrequency electromagnetic fields (RF-EMFs), are still unclear and only few studies reported about the effect of RFEMFs on self-renewal of neural progenitor cells. In this research, we investigated the influence of low-intensity RF-EMFs on Olfactory Ensheathing Cell (OEC) cultures, typical glia cells showing characteristics of stem cells. Cell cultures were exposed, in far-field condition, at 900 MHz continuous and amplitude modulated EMFs for 10, 15 and 20 min at 37°C. The expression of OEC marker (S-100), stem cell marker (Nestin), cytoskeletal proteins (GFAP and Vimentin), apoptotic pathway activation by Caspase-3 cleavage and cell viability, were evaluated. Surprisingly 20 min of exposure to continuous or amplitude modulated 900 MHz EMF induced a different and significant decrease in cell viability, some dynamic changes in the expression of the analysed markers and in the activation of the apoptotic pathway. [ABSTRACT FROM AUTHOR]