Standing wave oscillations in an electrocatalytic reaction

Experimental standing wave oscillations of the interfacial potential across an electrode have been observed in the electrocatalytic oxidation of formic acid on a Pt ring working electrode. The instantaneous potential distribution was monitored by means of equispaced potential microprobes along the electrode. The oscillatory standing waves spontaneously arose from a homogeneous stationary state prior to a Hopf bifurcation if the reference electrode was placed close to the working electrode. Reduced electrolyte concentrations resulted in aperiodic potential patterns, while the presence of a sufficiently large ohmic resistance completely suppressed spatial inhomogeneities. The experimental findings confirm numerical predictions of a reaction-migration formalism: under the chosen geometry, a long-range negative potential coupling between distant points across the ring electrode can lead to oscillatory potential domains of distinct phase. It is further shown that the occurrence of oscillatory standing waves can be rationalized as the electrochemical equivalent of Turing's second bifurcation (wave bifurcation). In the presence of an external resistance, the coupling becomes positive throughout and leads to spatial synchronization.

Testing genuine multipartite nonlocality in phase spacea

We demonstrate genuine three-mode nonlocality based on phase-space formalism. A Svetlichny-type Bell inequality is formulated in terms of the s-parametrized quasiprobability function. We test such a tool using exemplary forms of three-mode entangled states, identifying the ideal measurement settings required for each state. We thus verify the presence of genuine three-mode nonlocality that cannot be reproduced by local or nonlocal hidden variable models between any two out of three modes. In our results, GHZ- and W-type nonlocality can be fully discriminated. We also study the behavior of genuine tripartite nonlocality under the effects of detection inefficiency and dissipation induced by local thermal environments. Our formalism can be useful to test the sharing of genuine multipartite quantum correlations among the elements of some interesting physical settings, including arrays of trapped ions and intracavity ultracold atoms. DOI: 10.1103/PhysRevA.87.022123

Sequential measurement-based quantum computing with memories

We introduce a general scheme for sequential one-way quantum computation where static systems with long-living quantum coherence (memories) interact with moving systems that may possess very short coherence times. Both the generation of the cluster state needed for the computation and its consumption by measurements are carried out simultaneously. As a consequence, effective clusters of one spatial dimension fewer than in the standard approach are sufficient for computation. In particular, universal computation requires only a one-dimensional array of memories. The scheme applies to discrete-variable systems of any dimension as well as to continuous-variable ones, and both are treated equivalently under the light of local complementation of graphs. In this way our formalism introduces a general framework that encompasses and generalizes in a unified manner some previous system-dependent proposals. The procedure is intrinsically well suited for implementations with atom-photon interfaces.

Law and Society: Volume I: Historical development

The thriving and well-established field of Law and Society (also referred to as Sociolegal Studies) has diverse methodological influences; it draws on social-scientific and arts-based methods. The approach of scholars researching and teaching in the field often crosses disciplinary borders, but, broadly speaking, Law and Society scholarship goes behind formalism to investigate how and why law operates, or does not operate as intended, in society. By exploring law’s connections with broader social and political forces—both domestic and international—scholars gain valuable perspectives on ideology, culture, identity, and social life. Law and Society scholarship considers both the law in contexts, as well as contexts in law.
Law and Society flourishes today, perhaps as never before. Academic thinkers toil both on the mundane and the local, as well as the global, making major advances in the ways in which we think both about law and society. Especially over the last four decades, scholarly output has rapidly burgeoned, and this new title from Routledge’s acclaimed Critical Concepts in Law series answers the need for an authoritative reference collection to help users make sense of the daunting quantity of serious research and thinking.
Edited by the leading scholars in the field, Law and Society brings together in four volumes the vital classic and contemporary contributions. Volume I is dedicated to historical antecedents and precursors. The second volume covers methodologies and crucial themes. The third volume assembles key works on legal processes and professional groups, while the final volume of the collection focuses on substantive areas. Together, the volumes provide a one-stop ‘mini library’ enabling all interested researchers, teachers, and students to explore the origins of this thriving subdiscipline, and to gain a thorough understanding of where it is today.

Law and Society: Volume II: Methodologies and themes

The thriving and well-established field of Law and Society (also referred to as Sociolegal Studies) has diverse methodological influences; it draws on social-scientific and arts-based methods. The approach of scholars researching and teaching in the field often crosses disciplinary borders, but, broadly speaking, Law and Society scholarship goes behind formalism to investigate how and why law operates, or does not operate as intended, in society. By exploring law’s connections with broader social and political forces—both domestic and international—scholars gain valuable perspectives on ideology, culture, identity, and social life. Law and Society scholarship considers both the law in contexts, as well as contexts in law.
Law and Society flourishes today, perhaps as never before. Academic thinkers toil both on the mundane and the local, as well as the global, making major advances in the ways in which we think both about law and society. Especially over the last four decades, scholarly output has rapidly burgeoned, and this new title from Routledge’s acclaimed Critical Concepts in Law series answers the need for an authoritative reference collection to help users make sense of the daunting quantity of serious research and thinking.
Edited by the leading scholars in the field, Law and Society brings together in four volumes the vital classic and contemporary contributions. Volume I is dedicated to historical antecedents and precursors. The second volume covers methodologies and crucial themes. The third volume assembles key works on legal processes and professional groups, while the final volume of the collection focuses on substantive areas. Together, the volumes provide a one-stop ‘mini library’ enabling all interested researchers, teachers, and students to explore the origins of this thriving sub discipline, and to gain a thorough understanding of where it is today.

Law and Society: Volume III: Legal Processes and Professional Groups within the Legal Field

The thriving and well-established field of Law and Society (also referred to as Socio-legal Studies) has diverse methodological influences; it draws on social-scientific and arts-based methods. The approach of scholars researching and teaching in the field often crosses disciplinary borders, but, broadly speaking, Law and Society scholarship goes behind formalism to investigate how and why law operates, or does not operate as intended, in society. By exploring law’s connections with broader social and political forces—both domestic and international—scholars gain valuable perspectives on ideology, culture, identity, and social life. Law and Society scholarship considers both the law in contexts, as well as contexts in law.
Law and Society flourishes today, perhaps as never before. Academic thinkers toil both on the mundane and the local, as well as the global, making major advances in the ways in which we think both about law and society. Especially over the last four decades, scholarly output has rapidly burgeoned, and this new title from Routledge’s acclaimed Critical Concepts in Law series answers the need for an authoritative reference collection to help users make sense of the daunting quantity of serious research and thinking.
Edited by the leading scholars in the field, Law and Society brings together in four volumes the vital classic and contemporary contributions. Volume I is dedicated to historical antecedents and precursors. The second volume covers methodologies and crucial themes. The third volume assembles key works on legal processes and professional groups, while the final volume of the collection focuses on substantive areas. Together, the volumes provide a one-stop ‘mini library’ enabling all interested researchers, teachers, and students to explore the origins of this thriving sub discipline, and to gain a thorough understanding of where it is today.

Law and Society: Volume IV: Substantive Areas

The thriving and well-established field of Law and Society (also referred to as Sociolegal Studies) has diverse methodological influences; it draws on social-scientific and arts-based methods. The approach of scholars researching and teaching in the field often crosses disciplinary borders, but, broadly speaking, Law and Society scholarship goes behind formalism to investigate how and why law operates, or does not operate as intended, in society. By exploring law’s connections with broader social and political forces—both domestic and international—scholars gain valuable perspectives on ideology, culture, identity, and social life. Law and Society scholarship considers both the law in contexts, as well as contexts in law.
Law and Society flourishes today, perhaps as never before. Academic thinkers toil both on the mundane and the local, as well as the global, making major advances in the ways in which we think both about law and society. Especially over the last four decades, scholarly output has rapidly burgeoned, and this new title from Routledge’s acclaimed Critical Concepts in Law series answers the need for an authoritative reference collection to help users make sense of the daunting quantity of serious research and thinking.
Edited by the leading scholars in the field, Law and Society brings together in four volumes the vital classic and contemporary contributions. Volume I is dedicated to historical antecedents and precursors. The second volume covers methodologies and crucial themes. The third volume assembles key works on legal processes and professional groups, while the final volume of the collection focuses on substantive areas. Together, the volumes provide a one-stop ‘mini library’ enabling all interested researchers, teachers, and students to explore the origins of this thriving sub discipline, and to gain a thorough understanding of where it is today.

Generalized Langevin equation: An efficient approach to nonequilibrium molecular dynamics of open systems

The generalized Langevin equation (GLE) has been recently suggested to simulate the time evolution of classical solid and molecular systems when considering general nonequilibrium processes. In this approach, a part of the whole system (an open system), which interacts and exchanges energy with its dissipative environment, is studied. Because the GLE is derived by projecting out exactly the harmonic environment, the coupling to it is realistic, while the equations of motion are non-Markovian. Although the GLE formalism has already found promising applications, e. g., in nanotribology and as a powerful thermostat for equilibration in classical molecular dynamics simulations, efficient algorithms to solve the GLE for realistic memory kernels are highly nontrivial, especially if the memory kernels decay nonexponentially. This is due to the fact that one has to generate a colored noise and take account of the memory effects in a consistent manner. In this paper, we present a simple, yet efficient, algorithm for solving the GLE for practical memory kernels and we demonstrate its capability for the exactly solvable case of a harmonic oscillator coupled to a Debye bath.

Transitionless quantum driving in open quantum systems

We extend the concept of superadiabatic dynamics, or transitionless quantum driving, to quantum open systems whose evolution is governed by a master equation in the Lindblad form. We provide the general framework needed to determine the control strategy required to achieve superadiabaticity. We apply our formalism to two examples consisting of a two-level system coupled to environments with time-dependent bath operators. 

Characterisation of Passive Intermodulation in Passive RF Devices with X-parameter

A novel approach to the modelling of passive intermodulation (PIM) generation in passive components with distributed weak nonlinearities is outlined. Based upon the formalism of X-parameters, it provides a unified framework for co-design of antenna beamforming networks, filters, combiners, phase shifters and other passive and active devices containing nonlinearities at RF front-end. The effects of discontinuities and complex circuit layouts can be efficiently evaluated with the aid of the equivalent networks of the canonical nonlinear elements. The main concepts are illustrated by examples of numerical simulations of PIM generation in the transmission lines and comparison with the measurement results.

Modeling relativistic soliton interactions in overdense plasmas: A perturbed nonlinear Schrodinger equation framework

We investigate the dynamics of localized solutions of the relativistic cold-fluid plasma model in the small but finite amplitude limit, for slightly overcritical plasma density. Adopting a multiple scale analysis, we derive a perturbed nonlinear Schrodinger equation that describes the evolution of the envelope of circularly polarized electromagnetic field. Retaining terms up to fifth order in the small perturbation parameter, we derive a self-consistent framework for the description of the plasma response in the presence of localized electromagnetic field. The formalism is applied to standing electromagnetic soliton interactions and the results are validated by simulations of the full cold-fluid model. To lowest order, a cubic nonlinear Schrodinger equation with a focusing nonlinearity is recovered. Classical quasiparticle theory is used to obtain analytical estimates for the collision time and minimum distance of approach between solitons. For larger soliton amplitudes the inclusion of the fifth-order terms is essential for a qualitatively correct description of soliton interactions. The defocusing quintic nonlinearity leads to inelastic soliton collisions, while bound states of solitons do not persist under perturbations in the initial phase or amplitude

MULTIPLE-SCATTERING EFFECTS IN ELECTRON HOLOGRAPHIC IMAGES

An exact multiple-scattering formalism is used to simulate a wave multiply scattered from a cluster, and this is used to provide a direct quantitative analysis of the influence of multiple scattering on holographic imaging. Although multiple scattering may help in identifying atomic positions in real space, we show that it does cause a loss of resolution. We also show that a filter function can considerably reduce the multiple-scattering contribution to holographic images.

DOMINANCE OF SHORT-RANGE-ORDER EFFECTS IN LOW-ENERGY ELECTRON-DIFFRACTION INTENSITY SPECTRA

Using low-energy electron-diffraction (LEED) formalism, we demonstrate theoretically that LEED I-V spectra are characterized mainly by short-range order. We also show experimentally that diffuse LEED (DLEED) I-V spectra can be accurately measured from a disordered system using a video-LEED system even at very low coverage. These spectra demonstrate that experimental DLEED I-V spectra from disordered systems may be used to determine local structures. As an example, it is shown that experimental DLEED I-V spectra from K/Co {1010BAR} at potassium coverages of 0.07, 0.1, and 0.13 monolayer closely resemble calculated and experimental LEED I-V spectra for a well-ordered Co{1010BAR}-c(2X2)-K superstructure, leading to the conclusion that at low coverages, potassium atoms are located in the fourfold-hollow sites and that there is no large bond-length change with coverage.

Belief change with noisy sensing in the situation calculus

Situation calculus has been applied widely in arti?cial intelligence to model and reason about actions and changes in dynamic systems. Since actions carried out by agents will cause constant changes of the agents’ beliefs, how to manage
these changes is a very important issue. Shapiro et al. [22] is one of the studies that considered this issue. However, in this framework, the problem of noisy sensing, which often presents in real-world applications, is not considered. As a
consequence, noisy sensing actions in this framework will lead to an agent facing inconsistent situation and subsequently the agent cannot proceed further. In this paper, we investigate how noisy sensing actions can be handled in iterated
belief change within the situation calculus formalism. We extend the framework proposed in [22] with the capability of managing noisy sensings. We demonstrate that an agent can still detect the actual situation when the ratio of noisy sensing actions vs. accurate sensing actions is limited. We prove that our framework subsumes the iterated belief change strategy in [22] when all sensing actions are accurate. Furthermore, we prove that our framework can adequately handle belief introspection, mistaken beliefs, belief revision and belief update even with noisy sensing, as done in [22] with accurate sensing actions only.

Communication Nonlinearities Techniques for Analysis of Passive Intermodulation

The X-parameter based nonlinear modelling tools have been adopted as the foundation for the advanced methodology
of experimental characterisation and design of passive nonlinear devices. Based upon the formalism of the Xparameters,
it provides a unified framework for co-design of antenna beamforming networks, filters, phase shifters and
other passive and active devices of RF front-end, taking into account the effect of their nonlinearities. The equivalent
circuits of the canonical elements are readily incorporated in the models, thus enabling evaluation of PIM effect on the
performance of individual devices and their assemblies. An important advantage of the presented methodology is its
compatibility with the industry-standard established commercial RF circuit simulator Agilent ADS.
The major challenge in practical implementation of the proposed approach is concerned with experimental retrieval of the X-parameters for canonical passive circuit elements. To our best knowledge commercial PIM testers and practical laboratory test instruments are inherently narrowband and do not allow for simultaneous vector measurements at the PIM and harmonic frequencies. Alternatively, existing nonlinear vector analysers (NVNA) support X-parameter measurements in a broad frequency bands with a range of stimuli, but their dynamic range is insufficient for the PIM characterisation in practical circuits. Further opportunities for adaptation of the X-parameters methodology to the PIM
characterisation of passive devices using the existing test instruments are explored.