A robust sar speckle tracking workflow for measuring and interpreting the 3d surface displacement of landslides

We present a workflow for investigating large, slow‐moving landslides which combines the synthetic aperture radar (SAR) technique, GIS post‐processing, and airborne laser scanning (ALS), and apply it to Fels landslide in Alaska, US. First, we exploit a speckle tracking (ST) approach to derive the easting, northing, and vertical components of the displacement vectors across the rock slope for two five‐year windows, 2010–2015 and 2015–2020. Then, we perform post‐processing in a GIS environment to derive displacement magnitude, trend, and plunge maps of the landslide area. Finally, we compare the ST‐derived displacement data with structural lineament maps and profiles extracted from the ALS dataset. Relying on remotely sensed data, we estimate that the thickness of the slide mass is more than 100 m and displacements occur through a combination of slumping at the toe and planar sliding in the central and upper slope. Our approach provides information and interpretations that can assist in optimizing and planning fieldwork activities and site investigations at landslides in remote locations

Describing Art - An Interdisciplinary Approach to the Effects of Speaking on Gaze Movements during the Beholding of Paintings

Ever since the Renaissance speaking about paintings has been a fundamental approach for beholders, especially experts. However, it is unclear whether and how speaking about art modifies the way we look at it and this was not yet empirically tested. The present study investigated to the best of our knowledge for the first time in what way speaking modifies the patterns of fixations and gaze movements while looking at paintings. Ninety nine university students looked at four paintings selected to cover different art historical typologies for periods of 15 minutes each while gaze movement data were recorded. After 10 minutes, the participants of the experimental group were asked open questions about the painting. Speaking dramatically reduced the duration of fixations and painting area covered by fixations while at the same time increasing the frequencies of fixations, gaze length and the amount of repeated transitions between fixation clusters. These results suggest that the production of texts as well-organised sequences of information, structures the gazes of art beholders by making them quicker, more focused and better connected

Density-induced BCS to Bose-Einstein crossover

We investigate the zero-temperature BCS to Bose-Einstein crossover at the mean-field level, by driving it with the attractive potential and the particle density.We emphasize specifically the role played by the particle density in this crossover.Three different interparticle potentials are considered for the continuum model in three spatial dimensions, while both s- and d-wave solutions are analyzed for the attractive (extended) Hubbard model on a two-dimensional square lattice. For this model the peculiar behavior of the crossover for the d-wave solution is discussed.In particular, in the strong-coupling limit when approaching half filling we evidence the occurrence of strong correlations among antiparallel-spin fermions belonging to different composite bosons, which give rise to a quasi-long-range antiferromagnetic order in this limit.Comment: 10 pages, 5 enclosed figure

Hidden spin-current conservation in 2d Fermi liquids

We report the existence of regimes of the two dimensional Fermi liquid that show unusual conservation of the spin current and may be tuned by varying some parameter like the density of fermions. We show that for reasonable models of the effective interaction the spin current may be conserved in general in 2d, not only for a particular regime. Low temperature spin waves propagate distinctively in these regimes and entirely new ``spin-acoustic'' modes are predicted for scattering-dominated temperature ranges. These new high-temperature propagating spin waves provide a clear signature for the experimental search of such regimes.Comment: 4 pages, no figures, revised version, accepted for pub. in the PR

Theory of the temperature and doping dependence of the Hall effect in a model with x-ray edge singularities in d=oo

We explain the anomalous features in the Hall data observed experimentally in the normal state of the high-Tc superconductors. We show that a consistent treatment of the local spin fluctuations in a model with x-ray edge singularities in d=oo reproduces the temperature and the doping dependence of the Hall constant as well as the Hall angle in the normal state. The model has also been invoked to justify the marginal-Fermi-liquid behavior, and provides a consistent explanation of the Hall anomalies for a non-Fermi liquid in d=oo.Comment: 5 pages, 4 figures, To appear in Phys. Rev. B, title correcte

On the Fulde-Ferrell State in Spatially Isotropic Superconductors

Effects of superconducting fluctuations on the Fulde-Ferrell (FF) state are discussed in a spatially isotropic three-dimensional superconductor under a magnetic field. For this system, Shimahara recently showed that within the phenomenological Ginzburg-Landau theory, the long-range order of the FF state is suppressed by the phase fluctuation of the superconducting order parameter. [H. Shimahara: J. Phys. Soc. Jpn. {\bf 67} (1998) 1872, Physica B {\bf 259-261} (1999) 492] In this letter, we investigate this instability of the FF state against superconducting fluctuations from the microscopic viewpoint, employing the theory developed by Nozi\'eres and Schmitt-Rink in the BCS-BEC crossover field. Besides the absence of the second-order phase transition associated with the FF state, we show that even if the pairing interaction is weak, the shift of the chemical potential from the Fermi energy due to the fluctuations is crucial near the critical magnetic field of the FF state obtained within the mean-field theory.Comment: 11 pages, 1 figur

Nonperturbative XY-model approach to strong coupling superconductivity in two and three dimensions

For an electron gas with delta-function attraction we investigate the crossover from weak- to strong-coupling supercoductivity in two and three dimensions. We derive analytic expressions for the stiffness of phase fluctuations and set up effective XY-models which serve to determine nonperturbatively the temperature of phase decoherence where superconductivity breaks down. We find the transition temperature T_c as a monotonous function of the coupling strength and carrier density both in two and three dimensions, and give analytic formulas for the merging of the temperature of phase decoherence with the temperature of pair formation in the weak-coupling limit.Comment: Few typos corrected. Emails that were sent to the address [email protected] in June and July 1999 were lost in a computer crash, so if your comments were not answered please send them once mor

Superconducting transitions from the pseudogap state: d-wave symmetry, lattice, and low-dimensional effects

We investigate the behavior of the superconducting transition temperature within a previously developed BCS-Bose Einstein crossover picture. This picture, based on a decoupling scheme of Kadanoff and Martin, further extended by Patton, can be used to derive a simple form for the superconducting transition temperature in the presence of a pseudogap. We extend previous work which addressed the case of s-wave pairing in jellium, to explore the solutions for T_c as a function of variable coupling in more physically relevant situations. We thereby ascertain the effects of reduced dimensionality, periodic lattices and a d-wave pairing interaction. Implications for the cuprate superconductors are discussed.Comment: REVTeX, 11 pages, 6 EPS figures included, Replace with published versio