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Regulatory frameworks for the use of AI are emerging. However, they trail behind the fast-evolving malicious AI technologies that can quickly cause lasting societal damage. In response, we introduce a pioneering Assistive AI framework designed to enhance human decision-making capabilities. This framework aims to establish a trust network across various fields, especially within legal contexts, serving as a proactive complement to ongoing regulatory efforts. Central to our framework are the principles of privacy, accountability, and credibility. In our methodology, the foundation of reliability of information and information sources is built upon the ability to uphold accountability, enhance security, and protect privacy. This approach supports, filters, and potentially guides communication, thereby empowering individuals and communities to make well-informed decisions based on cutting-edge advancements in AI. Our framework uses the concept of Boards as proxies to collectively ensure that AI-assisted decisions are reliable, accountable, and in alignment with societal values and legal standards. Through a detailed exploration of our framework, including its main components, operations, and sample use cases, the paper shows how AI can assist in the complex process of decision-making while maintaining human oversight. The proposed framework not only extends regulatory landscapes but also highlights the synergy between AI technology and human judgement, underscoring the potential of AI to serve as a vital instrument in discerning reality from fiction and thus enhancing the decision-making process. Furthermore, we provide domain-specific use cases to highlight the applicability of our framework., Comment: 37 pages, 6 figures; Changes: Revised references (k-anonimity)

Quantum confinement of graphene carriers is an effective way to engineer its properties. It is commonly realized through physical edges that are associated with the deterioration of mobility and strong suppression of plasmon resonances. Here, we demonstrate a simple, large-area, edge-free nanostructuring technique, based on amplifying random nanoscale structural corrugations to a level where they efficiently confine carriers, without inducing significant inter-valley scattering. This soft confinement, allows the low-loss lateral ultra-confinement of graphene plasmons, scaling up their resonance frequency from native terahertz to commercially relevant visible range. Visible graphene plasmons localized into nanocorrugations mediate several orders of magnitude stronger light-matter interactions (Raman enhancement) than those previously achieved with graphene, enabling the detection of specific molecules from femtomolar solutions or ambient air. Moreover, nanocorrugated graphene sheets also support propagating visible plasmon modes revealed by scanning near-field optical microscopy observation of their interference patterns.

Probing the anomalous nanoscale intermixing using molecular dynamics (MD) simulations in Pt/Ti bilayer we characterize the superdiffusive nature of interfacial atomic transport. In particular, the low-energy ($0.5$ keV) ion-sputtering induced transient enhanced intermixing has been studied by MD simulations. {\em Ab initio} density functional calculations have been used to check and reparametrize the employed heteronuclear interatomic potential. We find a robust intermixing in Pt/Ti driven by nanoscale mass-anisotropy . The sum of the square of atomic displacements $\langle R^2 \rangle$ asymptotically scales nonlinearly ($\langle R^2 \rangle \propto t^2$), where $t$ is the time of ion-sputtering, respectively which is the fingerprint of superdiffusive features. This anomalous behavior explains the high diffusity tail in the concentration profile obtained by Auger electron spectroscopy depth profiling (AES-DP) analysis in Pt/Ti bilayer (reported in ref.: P. S\"ule, et al., J. Appl. Phys., 101, 043502 (2007)). In Ti/Pt bilayer a linear time scaling of $\langle R^2 \rangle \propto t$ has been found at the Ti/Pt interface indicating the suppression of superdiffusive features. These findings are inconsistent with the standard ion-mixing models. Instead a simple accelerative effect of the downward fluxes of energetic particles on the unidirectional fluxes of preferential intermixing of Pt atoms seems to explain the enhancement of interfacial broadening in Pt/Ti. Contrary to this in Ti/Pt the fluxes of recoils are in counterflow with intermixing Pt atoms and hence slows down the nanoscale mass-effect driven ballistic preferential mobility of Pt atoms., Comment: 12 pages, 5 figures, 1 table, written in 2007, uploaded this year. arXiv admin note: text overlap with arXiv:cond-mat/0605566, arXiv:0802.2220

The crossover behavior of various models exhibiting phase transition to absorbing phase with parity conserving class has been investigated by numerical simulations and cluster mean-field method. In case of models exhibiting Z_2 symmetric absorbing phases (the NEKIMCA and Grassberger's A stochastic cellular automaton) the introduction of an external symmetry breaking field causes a crossover to kink parity conserving models characterized by dynamical scaling of the directed percolation (DP) and the crossover exponent: 1/\phi ~ 0.53(2). In case an even offspringed branching and annihilating random walk model (dual to NEKIMCA) the introduction of spontaneous particle decay destroys the parity conservation and results in a crossover to the DP class characterized by the crossover exponent: 1/\phi\simeq 0.205(5). The two different kinds of crossover operators can't be mapped onto each other and the resulting models show a diversity within the DP universality class in one dimension. These 'sub-classes' differ in cluster scaling exponents., Comment: 6 pages, 6 figures, accepted version in PRE

Probing the anomalous nanoscale intermixing using molecular dynamics (MD) simulations in Pt/Ti bilayer we reveal the superdiffusive nature of interfacial atomic transport. It is shown that the Pt atoms undergo anomalous atomic transport across the anisotropic interface of Pt/Ti with suprisingly high rates which can be characterized as L\'evy flights. L\'evy flight is not a unique phenomenon in nature, however, no such events have been reported yet for bulk interdiffusion. In particular, the low-energy (0.5 keV) ion-sputtering induced transient enhanced intermixing has been studied by MD simulations. Ab initio density functional calculations have been used to check and reparametrize the employed heteronuclear interatomic potential. The L\'evy-intermixing behavior explains the high diffusity tail in the concentration profile obtained by Auger electron spectroscopy depth profiling (AES-DP) analysis in Pt/Ti bilayer (reported in ref.: P. S\"ule, {\em et al.}, J. Appl. Phys., {\bf 101}, 043502 (2007))., Comment: 4 pages, 3 figures

Large-scale Monte Carlo simulations are used to explore the effect of quenched disorder on one dimensional, non-equilibrium kinetic Ising models with locally broken spin symmetry, at zero temperature (the symmetry is broken through spin-flip rates that differ for '+' and '-' spins). The model is found to exhibit a continuous phase transition to an absorbing state. The associated critical behavior is studied at zero branching rate of kinks, through analysis spreading of '+' and '-' spins and, of the kink density. Impurities exert a strong effect on the critical behavior only for a particular choice of parameters, corresponding to the strongly spin-anisotropic kinetic Ising model introduced by Majumdar et al. Typically, disorder effects become evident for impurity strengths such that diffusion is nearly blocked. In this regime, the critical behavior is similar to that arising, for example, in the one-dimensional diluted contact process, with Griffiths-like behavior for the kink density. We find variable cluster exponents, which obey a hyperscaling relation, and are similar to those reported by Cafiero et al. We also show that the isotropic two-component AB -> 0 model is insensitive to reaction-disorder, and that only logarithmic corrections arise, induced by strong disorder in the diffusion rate., Comment: 10 pages, 13 figures. Final, accepted form in PRE, including a new table summarizing the moldes

The ion-sputtering induced intermixing is studied by Monte-Carlo TRIM, molecular dynamics (MD) simulations, and Auger electron spectroscopy depth profiling (AES-DP) analysis in Pt/Ti/Si substrate (Pt/Ti) and Ta/Ti/Pt/Si substrate (Ti/Pt) multilayers. Experimental evidence is found for the asymmetry of intermixing in Pt/Ti, and in Ti/Pt. In Ti/Pt we get a much weaker interdiffusion than in Pt/Ti. The unexpected enhancement of the interdiffusion of the Pt atoms into the Ti substrate has also been demonstrated by simulations. We are able to capture the essential features of intermixing using TRIM and MD simulations for ion-beam sputtering and get reasonable values for interface broadening which can be compared with the experimental measurements. However, the origin of the asymmetry remains poorly understood yet., Comment: 7 pages, 3 figures, 1 table, submitted to JAP, fig1a,1b are excluded do to size limit problem (can be seen at http://www.mfa.kfki.hu/~sule/animations/ptti.htm)

The ion-sputtering induced transient enhanced intermixing has been studied by molecular dynamics (MD) simulations in Pt/Ti and its anomalous nature has been explained as a superdiffusive transient enhanced interdiffusion. We find ballistic mixing and a robust mass effect in Pt/Ti. The sum of the square of atomic displacements ($$) asymptotically grows nonlinearily and scales as $N^2$ and $\sim t^2$, where $N$ and $t$ are the ion-number fluence and the time of ion-sputtering, respectively. This anomalous behavior explains the high diffusity tail in the concentration profile obtained by Auger electron spectroscopy depth profiling (AES-DP) analysis in Pt/Ti/Si substrate (Pt/Ti) multilayer. In Ta/Ti/Pt/Si multilayer we find a linear time scaling of $ \propto t$ at the Ti/Pt interface indicating the suppression of superdiffusive features. We propose a qualitative explanation based on the accelerative effect of nonlinear forces provbided by the anharmonic host lattice., Comment: 8 pages, 4 figures, RevTex format

The ion-bombardment induced evolution of intermixing is studied by molecular dynamics simulations and by Auger electron spectroscopy depth profiling analysis (AESD) in Cu/Co multilayer. It has been shown that from AESD we can derive the low-energy mixing rate and which can be compared with the simulated values obtained by molecular dynamics (MD) simulations. The overall agreement is reasonably good hence MD can hopefuly be used to estimate the rate of intermixing in various interface systems., Comment: 3 pages, 2 figures

A stochastic cellular automaton exhibiting parity conserving class transition has been investigated in the presence of quenched spatial disorder by large scale simulations. Numerical evidence has been found that weak disorder causes irrelevant perturbation for the universal behavior of the transition and the absorbing phase of this model. This opens up the possibility for experimental observation of the critical behavior of a nonequilibrium phase transition to absorbing state. For very strong disorder the model breaks up to blocks with exponential size distribution and continuously changing critical exponents are observed. For strong disorder the randomly distributed diffusion walls introduce another transition within the inactive phase of the model, in which residual particles survive the extinction. The critical dynamical behavior of this transition has been explored., Comment: 7 pages, 10 figures (included), 2 tables, accepted for publication in PRE

The ion-bombardment induced evolution of intermixing is studied by molecular dynamics simulations and by Auger electron spectroscopy depth profiling analysis (AESD) in Cu/Co multilayer. It has been shown that from AESD we can derive the low-energy mixing rate and which can be compared with the simulated values obtained by molecular dynamics (MD) simulations.The overall agreement is reasonably good hence MD can hopefully be used to estimate the rate of intermixing in various interface systems., Comment: 3 pages, 3 figures

The ion-sputtering induced intermixing is studied by molecular dynamics (MD) simulations and by Auger electron spectroscopy depth profiling (AES-DP) analysis in Pt/Ti/Si substrate (Pt/Ti) and Ta/Ti/Pt/Si substrate (Ti/Pt) multilayers. Experimental evidence is found for the asymmetry of intermixing in Pt/Ti and in Ti/Pt. An unexpected enhancement of the injection of the heavy Pt atoms into the Ti substrate is observed both by AES-DP and by MD simulations. In Ti/Pt we get a much weaker interdiffusion than in Pt/Ti. The asymmetry is explained by the backscattering of hyperthermal particles at the mass-anisotropic interface and which is reproduced by computer atomistic simulations. The AES-DP measurements support our earlier predictions (P. S\"ule, M. Menyh\'ard, Phys. Rev., {\bf B71}, 113413 (2005)) obtained for mass-anisotropic bilayers., Comment: 4 pages, 4 figures, sule@mfa.kfki.hu

Molecular dynamics simulations have been used to study the mechanism of ion beam mixing in metal bilayers. We are able to explain the ion induced low-temperature phase stability and melting behavior of bilayers using only a simple ballistic picture up to 10 keV ion energies. The atomic mass ratio of the overlayer and the substrate constituents seems to be a key quantity in understanding atomic mixing. The critical bilayer mass ratio of $\delta < 0.33$ is required for the occurrence of a thermal spike (local melting) with a lifetime of $\tau > 0.3$ ps at low-energy ion irradiation (1 keV) due to a ballistic mechanism. The existing experimental data follow the same trend as the simulated values., Comment: 4 pages, 4 figures, preprint

Molecular dynamics simulations have been used to study the driving force of ion irradiation induced interfacial mixing in metal bilayers in which the relative mass of the constituents is considerable. We find no apparent effect of chemical forces, such as heat of mixing or cohesive energy up to 8 keV ion energy, although a considerable number of liquid and high energy particles (hot atoms) persist up to even 20 ps during the thermal spike. This result is in direct conflict with the widely accepted theory of thermal spike mixing (chemical interdiffusion model). The supersaturation of vacancies also occurs and which induces a thermally activated intermixing of the lighter constituent of the bilayer. The delay and the decoupling of the intermixing of the light constituent is explained as a backscattering effect at the interface: the interface acts as a diffusional barrier for high energy particles due to the large difference in atomic masses. The heavier atoms are predominantly ejected to the overlayer at the beginning of the thermal spike while the light atoms are injected to the bulk at the beginning of the cooling period (in Ti/Pt) or during the thermal spike with some time delay (Al/Pt)., Comment: 8 pages, 6 figures

Molecular dynamics simulations have been used to study a collective atomic transport phenomenon by repeated Ar$^+$ irradiations in the Ti/Pt interfacial system. The ion-induced injection of surface atoms to the bulk, the ejection of bulk atoms to the top layers together with surface erosion is strongly enhanced by interfacial mixing. This process leads to a dense interfacial material, and broadening of the interface region. The process scales with the relative difference of the atomic masses. We find that surface roughening and interfacial mixing is strongly coupled via an enhanced counterflow material transport normal to the surface which might be a novel surface damage mechanism. This cooperative phenomenon is active when the bilayer system is subjected to a high dose ion irradiation (multiple ion irradiations) and leads to surface cavity growth., Comment: 6 pages, 6 figures. accepted in Nucl. Instrum. Meth. B

Numerical and theoretical studies of a one-dimensional spin model with locally broken spin symmetry are presented. The multi-species annihilating random walk transition found at zero branching rate previously is investigated now concerning the cluster behaviour of the underlying spins. Generic power law behaviors are found, besides the phase transition point, also in the active phase with fulfillment of the hyperscaling law. On the other hand scaling laws connecting bulk- and cluster exponents are broken - a possibility in no contradiction with basic scaling assumptions because of the missing absorbing phase., Comment: 7 pages, 6 figures, final form to appear in PRE Nov.2003

Molecular dynamics simulations have been used to obtain the three-dimensional distribution of interfacial mixing and cascade defects in Ti/Pt multilayer system due to single 1 keV $Ar^+$ impacts at grazing angle of incidence. The Ti/Pt system was chosen because of its relatively high heat of mixing in the binary alloy and therefore a suitable candidate for testing the effect of heat of mixing on ion-beam mixing. However, the calculated mixing profile is not sensitive to the heat of mixing. Therefore the thermal spike model of mixing is not fully supported under these irradiation conditions. Instead we found that the majority of mixing occurs after the thermal spike during the relaxation process. These conclusions are supported by liquid, vacancy as well as adatom analysis. The interfacial mixing is in various aspects anomalous in this system: the time evolution of mixing is leading to a phase delay for Ti mixing, and Pt exhibits an unexpected double peaked mixing evolution. The reasons to these effects are discussed., Comment: 7 pages, 12 figures, Nucl. Instr. Meth. B211, 524. (2003)

The effects of locally broken spin symmetry are investigated in one dimensional nonequilibrium kinetic Ising systems via computer simulations and cluster mean field calculations. Besides a line of directed percolation transitions, a line of transitions belonging to N-component, two-offspring branching annihilating random-walk class (N-BARW2) is revealed in the phase diagram at zero branching rate. In this way a spin model for N-BARW2 transitions is proposed for the first time., Comment: 6 pages, 5 figures included, 2 new tables added, to appear in PRE

We review the currently known universality classes of continuous phase transitions to absorbing states in nonequilibrium systems and present results of simulations and arguments to show how the blockades introduced by different particle species in one dimension cause new robust classes. Results of investigations on the dynamic scaling behavior of some bosonic spreading models are reported., Comment: New section added about simulation results of some one component bosonic spreading processes. Proc. of LAWNP01 Cocoyoc Mexico 2001. 13 pages 3 figures

The $A+A\to 0$, $B+B\to 0 $ process with exclusion between the different kinds is investigated here numerically. Before treating this model explicitly, we study the generalized Domany-Kinzel cellular automaton model of Hinrichsen on the line of the parameter space where only compact clusters can grow. The simplest version is treated with two absorbing phases in addition to the active one. The two kinds of kinks which arise in this case do not react, leading to kinetics differing from standard annihilating random walk of two species. Time dependent simulations are presented here to illustrate the differences caused by exclusion in the scaling properties of usually discussed characteristic quantities. The dependence on the density and composition of the initial state is most apparent. Making use of the parallelism between this process and directed percolation limited by a reflecting parabolic surface we argue that the two kinds of kinks exert marginal perturbation on each other leading to deviations from standard annihilating random walk behavior., Comment: 12 pages, 16 figures, small typos corrected, 2 references added

Nonequilibrium kinetic Ising models evolving under the competing effect of spin flips at zero temperature and Kawasaki-type spin-exchange kinetics at infinite temperature T are investigated here in one dimension from the point of view of phase transition and critical behaviour. Branching annihilating random walks with an even number of offspring (on the part of the ferromagnetic domain boundaries), is a decisive process in forming the steady state of the system for a range of parameters, in the family of models considered. A wide variety of quantities characterize the critical behaviour of the system. Results of computer simulations and of a generalized mean field theory are presented and discussed., Comment: 23 pages, 10 figures included

Compact directed percolation is known to appear at the endpoint of the directed percolation critical line of the Domany-Kinzel cellular automaton in 1+1 dimension. Equivalently, such transition occurs at zero temperature in a magnetic field H, upon changing the sign of H, in the one-dimensional Glauber-Ising model with well known exponents characterising spin-cluster growth. We have investigated here numerically these exponents in the non-equilibrium generalization (NEKIM) of the Glauber model in the vicinity of the parity-conserving phase transition point of the kinks. Critical fluctuations on the level of kinks are found to affect drastically the characteristic exponents of spreading of spins while the hyperscaling relation holds in its form appropriate for compact clusters., Comment: 7 pages, 7 figures embedded in the latex, final form before J.Phys.A publication

The damage spreading (DS) transitions of two one-dimensional stochastic cellular automata suggested by Grassberger (A and B) and the kinetic Ising model of Menyh\'ard (NEKIM) have been investigated on the level of kinks and spins. On the level of spins the parity conservation is not satisfied and therefore studying these models provides a convenient tool to understand the dependence of DS properties on symmetries. For the model B the critical point and the DS transition point is well separated and directed percolation damage spreading transition universality was found for spin damage as well as for kink damage in spite of the conservation of damage variables modulo 2 in the latter case. For the A stochastic cellular automaton, and the NEKIM model the two transition points coincide with drastic effects on the damage of spin and kink variables showing different time dependent behaviours. While the kink DS transition is continuous and shows regular PC class universality, the spin damage exhibits a discontinuous phase transition with compact clusters and PC like dynamical scaling ($\eta^,$), ($\delta_s$) and ($z_s$) exponents whereas the static exponents determined by FSS are consistent with that of the spins of the NEKIM model at the PC transition point. The generalised hyper-scaling law is satisfied., Comment: 11 pages, 20 figures embedded in the text, minor changes in the text, a new table and new references are added

One-dimensional non-equilibrium kinetic Ising models evolving under the competing effect of spin flips at zero temperature and nearest neighbour spin exchanges exhibiting a parity-conserving (PC) phase transition on the level of kinks are investigated here numerically from the point of view of the underlying spin system. The dynamical persistency exponent $\Theta$ and the exponent $lambda$ characterising the two-time autocorrelation function of the total magnetization under non-equilibrium conditions are reported. It is found that the PC transition has strong effect: the process becomes non-Markovian and the above exponents exhibit drastic changes as compared to the Glauber-Ising case., Comment: 6 pages, Latex, postscript figures included

One-dimensional non-equilibrium kinetic Ising models evolving under the competing effect of spin flips at zero temperature and nearest-neighbour spin exchanges exhibiting directed percolation-like parity conserving(PC) phase transition on the level of kinks are now further investigated, numerically, from the point of view of the underlying spin system. Critical exponents characterising its statics and dynamics are reported. It is found that the influence of the PC transition on the critical exponents of the spins is strong and the origin of drastic changes as compared to the Glauber-Ising case can be traced back to the hyperscaling law stemming from directed percolation(DP). Effect of an external magnetic field, leading to DP-type critical behaviour on the level of kinks, is also studied, mainly through the generalised mean field approximation., Comment: 15 pages, using RevTeX, 13 Postscript figures included, submitted to J.Phys.A, figures 12 and 13 fixed

A family of nonequilibrium kinetic Ising models, introduced earlier, evolving under the competing effect of spin flips at {\it zero temperature} and nearest neighbour random spin exchanges is further investigated here. By increasing the range of spin exchanges and/or their strength the nature of the phase transition 'Ising-to-active' becomes of (dynamic) mean-field type and a first order tricitical point is located at the Glauber ($\delta=0$) limit. Corrections to mean-field theory are evaluated up to sixth order in a cluster approximation and found to give good results concerning the phase boundary and the critical exponent $\beta$ of the order parameter which is obtained as $\beta\simeq1.0$., Comment: 15 pages, revtex file, figures available at request from odor@r1.atki.kfki.hu in postscript format, submitted to J.Phys.A

Nonequilibrium kinetic Ising models evolving under the competing effect of spin flips at zero temperature and nearest neighbour spin exchanges at $T=\infty$ are investigated numerically from the point of view of a phase transition. Branching annihilating random walk of the ferromagnetic domain boundaries determines the steady state of the system for a range of parameters of the model. Critical exponents obtained by simulation are found to agree, within error, with those in Grassberger's cellular automata., Comment: 10 pages, Latex, figures upon request, SZFKI 05/94