Scaling relations in three-dimensional disordered superconductors

1996 ◽  
Vol 39 (8) ◽  
pp. 845-845
Author(s):  
Vladimir N Zverev ◽  
Vsevolod F Gantmakher ◽  
V M Teplinskii
1996 ◽  
Vol 166 (8) ◽  
pp. 904
Author(s):  
Vladimir N. Zverev ◽  
Vsevolod F. Gantmakher ◽  
V.M. Teplinskii

1998 ◽  
Vol 12 (19) ◽  
pp. 763-773 ◽  
Author(s):  
Yong-Jihn Kim ◽  
K. J. Chang

We investigate the effect of weak localization on the transition temperatures of superconductors using Anderson's time-reversed scattered-state pairs, and show that disorder weakens electron–phonon interactions. With solving the BCS T c -equation, the calculated values for T c are in good agreement with experimental data for various two- and three-dimensional disordered superconductors. We find that the critical sheet resistance for the suppression of superconductivity in thin films does not satisfy the universal behavior but depends on sample, in good agreement with experiments.


2020 ◽  
Vol 11 (1) ◽  
Author(s):  
P. K. Bera ◽  
S. Majumdar ◽  
G. Ouillon ◽  
D. Sornette ◽  
A. K. Sood

AbstractThe flow behavior of soft materials below the yield stress can be rich and is not fully understood. Here, we report shear-stress-induced reorganization of three-dimensional solid-like soft materials formed by closely packed nematic domains of surfactant micelles and a repulsive Wigner glass formed by anisotropic clay nano-discs having ionic interactions. The creep response of both the systems below the yield stress results in angular velocity fluctuations of the shearing plate showing large temporal burst-like events that resemble seismic foreshocks-aftershocks data measuring the ground motion during earthquake avalanches. We find that the statistical properties of the quake events inside such a burst map on to the scaling relations for magnitude and frequency distribution of earthquakes, given by Gutenberg-Richter and Omori laws, and follow a power-law distribution of the inter-occurrence waiting time. In situ polarized optical microscopy reveals that during these events the system self-organizes to a much stronger solid-like state.


2019 ◽  
Vol 871 ◽  
pp. 1117-1138 ◽  
Author(s):  
Fatma Ayancik ◽  
Qiang Zhong ◽  
Daniel B. Quinn ◽  
Aaron Brandes ◽  
Hilary Bart-Smith ◽  
...  

Scaling laws for the thrust production and energetics of self-propelled or fixed-velocity three-dimensional rigid propulsors undergoing pitching motions are presented. The scaling relations extend the two-dimensional scaling laws presented in Moored & Quinn (AIAA J., 2018, pp. 1–15) by accounting for the added mass of a finite-span propulsor, the downwash/upwash effects from the trailing vortex system of a propulsor and the elliptical topology of shedding trailing-edge vortices. The novel three-dimensional scaling laws are validated with self-propelled inviscid simulations and fixed-velocity experiments over a range of reduced frequencies, Strouhal numbers and aspect ratios relevant to bio-inspired propulsion. The scaling laws elucidate the dominant flow physics behind the thrust production and energetics of pitching bio-propulsors, and they provide guidance for the design of bio-inspired propulsive systems.


2019 ◽  
Vol 57 (1) ◽  
pp. 157-187 ◽  
Author(s):  
Steven R. Cranmer ◽  
Amy R. Winebarger

The corona is a layer of hot plasma that surrounds the Sun, traces out its complex magnetic field, and ultimately expands into interplanetary space as the supersonic solar wind. Although much has been learned in recent decades from advances in observations, theory, and computer simulations, we still have not identified definitively the physical processes that heat the corona and accelerate the solar wind. In this review, we summarize these recent advances and speculate about what else is required to finally understand the fundamental physics of this complex system. Specifically: ▪ We discuss recent subarcsecond observations of the corona, some of which appear to provide evidence for tangled and braided magnetic fields and some of which do not. ▪ We review results from three-dimensional numerical simulations that, despite limitations in dynamic range, reliably contain sufficient heating to produce and maintain the corona. ▪ We provide a new tabulation of scaling relations for a number of proposed coronal heating theories that involve waves, turbulence, braiding, nanoflares, and helicity conservation. An understanding of these processes is important not only for improving our ability to forecast hazardous space-weather events but also for establishing a baseline of knowledge about a well-resolved star that is relevant to other astrophysical systems.


2017 ◽  
Vol 69 (1) ◽  
Author(s):  
Y. L. Young ◽  
C. M. Harwood ◽  
F. Miguel Montero ◽  
J. C. Ward ◽  
S. L. Ceccio

Ventilation is relevant to the performance, safety, and controllability of marine vessels, propulsors, and control surfaces that operate at or near the free surface. The objectives of this work are to (1) review the fundamental physics driving ventilation and its impact upon the hydrodynamic and structural response, and (2) discuss the scaling relations and its implications on the design and interpretation of reduced-scale studies. Natural ventilation occurs when the flow around a body forms a cavity that is open to the free surface. The steady flow regimes, hydrodynamic loads, and unsteady transition mechanisms of naturally ventilated flows are reviewed. Forced ventilation permits control of the cavity pressure and cavity shape, but can result in unsteady cavity pulsations. When a lifting surface is flexible, flow-induced deformations can increase the loading and the size of cavities, as well as lead to earlier ventilation formation. Ventilation tends to reduce the susceptibility of a lifting surface to static divergence. However, fluctuations of fluid added mass, damping, and disturbing forces caused by unsteady ventilation will change the structural resonance frequencies and damping, and may accelerate hydroelastic instabilities. Scaling relations are developed for both the hydrodynamic and hydroelastic response. Similarity in the three-dimensional (3D) ventilation pattern and hydrodynamic response requires simultaneous satisfaction of Froude number, cavitation number, and geometric similarity. However, Froude scaling complicates the selection of suitable model-scale material to achieve similarity in the dynamic hydroelastic response and material failure mechanisms between the model and full scale.


1966 ◽  
Vol 25 ◽  
pp. 227-229 ◽  
Author(s):  
D. Brouwer

The paper presents a summary of the results obtained by C. J. Cohen and E. C. Hubbard, who established by numerical integration that a resonance relation exists between the orbits of Neptune and Pluto. The problem may be explored further by approximating the motion of Pluto by that of a particle with negligible mass in the three-dimensional (circular) restricted problem. The mass of Pluto and the eccentricity of Neptune's orbit are ignored in this approximation. Significant features of the problem appear to be the presence of two critical arguments and the possibility that the orbit may be related to a periodic orbit of the third kind.


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