Transport and Noise Characteristics of Submicron High-Temperature Superconductor Grain-Boundary Junctions

We have investigated the transport and noise properties of submicron YBCO bicrystal grain-boundary junctions prepared using electron beam lithography. The junctions show an increased conductance for low voltages reminiscent of Josephson junctions having a barrier with high transmissivity. The voltage noise spectra are dominated by a few Lorentzian components. At low temperatures clear two-level random telegraph switching (RTS) signals are observable in the voltage vs time traces. We have investigated the temperature and voltage dependence of individual fluctuators both from statistical analysis of voltage vs time traces and from fits to noise spectra. A transition from tunneling to thermally activated behavior of individual fluctuators was clearly observed. The experimental results support the model of charge carrier traps in the barrier region.Comment: 4 pages, 4 figures, to be published in Appl. Phys. Let

Mathematical Models for Natural Gas Forecasting

It is vital for natural gas Local Distribution Companies (LDCs) to forecast their customers\u27 natural gas demand accurately. A significant error on a single very cold day can cost the customers of the LDC millions of dollars. This paper looks at the financial implication of forecasting natural gas, the nature of natural gas forecasting, the factors that impact natural gas consumption, and describes a survey of mathematical techniques and practices used to model natural gas demand. Many of the techniques used in this paper currently are implemented in a software GasDayTM, which is currently used by 24 LDCs throughout the United States, forecasting about 20% of the total U.S. residential, commercial, and industrial consumption. Results of GasDay\u27sTM forecasting performance also is presented

Quantum Fluctuations Driven Orientational Disordering: A Finite-Size Scaling Study

The orientational ordering transition is investigated in the quantum generalization of the anisotropic-planar-rotor model in the low temperature regime. The phase diagram of the model is first analyzed within the mean-field approximation. This predicts at $T=0$ a phase transition from the ordered to the disordered state when the strength of quantum fluctuations, characterized by the rotational constant $\Theta$, exceeds a critical value $\Theta_{\rm c}^{MF}$. As a function of temperature, mean-field theory predicts a range of values of $\Theta$ where the system develops long-range order upon cooling, but enters again into a disordered state at sufficiently low temperatures (reentrance). The model is further studied by means of path integral Monte Carlo simulations in combination with finite-size scaling techniques, concentrating on the region of parameter space where reentrance is predicted to occur. The phase diagram determined from the simulations does not seem to exhibit reentrant behavior; at intermediate temperatures a pronounced increase of short-range order is observed rather than a genuine long-range order.Comment: 27 pages, 8 figures, RevTe

Enticing Local Governments to Produce FAIR Freedom of Information Act Dossiers

Government transparency is central in a democratic society, and increasingly governments at all levels are required to publish records and data either proactively, or upon so-called Freedom of Information (FIA) requests. However, public bodies who are required by law to publish many of their documents turn out to have great difficulty to do so. And what they publish often is in a format that still breaches the requirements of the law, stipulating principles comparable to the FAIR data principles. Hence, this demo is addressing a timely problem: the FAIR publication of FIA dossiers, which is obligatory in The Netherlands since May 1st 2022.</p

Melting of icosahedral gold nanoclusters from molecular dynamics simulations

Molecular dynamics simulations show that gold clusters with about 600--3000 atoms crystallize into a Mackay icosahedron upon cooling from the liquid. A detailed surface analysis shows that the facets on the surface of the Mackay icosahedral gold clusters soften but do not premelt below the bulk melting temperature. This softening is found to be due to the increasing mobility of vertex and edge atoms with temperature, which leads to inter-layer and intra-layer diffusion, and a shrinkage of the average facet size, so that the average shape of the cluster is nearly spherical at melting.Comment: 40 pages, 27 figure

Elementary particles of conventional field theory as Regge poles. III

It is shown that an elementary particle of conventional field theory may, under certain conditions, lie on a Regge trajectory. These conditions are that the system contain a "nonsense" channel at the angular momentum of the particle and that the Born approximation scattering amplitude factor in a well-defined way. They are satisfied by a spin ½ fermion interacting through a conserved current with a spin one neutral boson. The particle in question is the fermion