scispace - formally typeset
Search or ask a question
Topic

Slab

About: Slab is a research topic. Over the lifetime, 31617 publications have been published within this topic receiving 318693 citations.


Papers
More filters
Journal ArticleDOI
TL;DR: The focusing of optical beams within an inhomogeneous dielectric metamaterial with space-variant polarizability is experimentally demonstrated for the first time by etching subwavelength structures into a Silicon slab.
Abstract: We experimentally demonstrate for the first time the focusing of optical beams within an inhomogeneous dielectric metamaterial with space-variant polarizability, implemented by etching subwavelength structures into a Silicon slab. Light focusing is obtained by creating an artificial slab material with graded refractive index profile. The local refractive index within the slab is modulated by controlling the duty cycle of the subwavelength structures. The demonstrated metamaterial based component can be integrated with various other building blocks towards the realization of devices and systems in free space optics on a chip configuration.

123 citations

Journal ArticleDOI
TL;DR: In this paper, periodic density functional theory (DFT) based on plane waves and Hartree−Fock (HF) calculations using slabs separated by vacuum gaps were carried out to model the H2O−TiO2 (rutile) (110) interface.
Abstract: Periodic density functional theory (DFT) based on plane waves (PW) and Hartree−Fock (HF) based on the linear combination of atomic orbitals (LCAO) calculations using slabs separated by vacuum gaps were carried out to model the H2O−TiO2 (rutile) (110) interface. Positions of all atoms were allowed to relax except atoms in the central layer of the slab. Both associative and dissociative adsorption mechanisms were considered for half-monolayer and monolayer coverages. Five different orientations of H2O molecules on the TiO2 surface were studied to determine the most energetically favorable water positions for the associative mechanism. Two slab thicknesses (three Ti layers and five Ti layers) were chosen to test the effect of slab depth on calculated surface structures and adsorption energies. Results indicate that associative adsorption is favorable by −8 to −20 kJ/mol/H2O depending on the slab thickness for full-monolayer coverage. Embedded cluster HF calculations were also performed for comparison. Adsorp...

122 citations

Journal ArticleDOI
TL;DR: In this paper, a 3D thermo-mechanical numerical joint model of continental collision, oceanic subduction and slab tearing is presented, which allows self-consistent reproduction of first-order Tethyan tectonic structures such as back-arc rifting and large-scale strike-slip faults accommodating continental escape.

122 citations

Journal ArticleDOI
TL;DR: In this article, the authors interpret these anisotropic patterns, also observed in laboratory experiment, as toroidal mantle flow induced by rollback subduction, and interpret them as a sign of active mantle flow.
Abstract: [1] SKS-wave birefringence is likely caused by ongoing and/or fossil mantle flow. Splitting parameters in the southern Tyrrhenian subduction zone define a quite complex pattern of fast directions with large delay times up to 2.7 s. Fast directions are prevalently trench parallel below the slab and rotate to trench normal at the western edge of the slab depicting a ring around it. We interpret these anisotropic patterns, also observed in laboratory experiment, as toroidal mantle flow induced by rollback subduction.

122 citations

Journal ArticleDOI
TL;DR: In this paper, the average shear stress in the top 100 km of the subduction shear zone of the Tonga and Mariana subduction system is calculated using a single differential equation.
Abstract: Summary. Because there is secondary sea-floor spreading in the Tonga and Mariana subduction systems, the island arcs are separate plates. Horizontal forces on the two sides of the arc must balance, and the maximum force on the back-arc side can be calculated from a lithostatic ridge model. This, in combination with gravity data, allows calculation of the average shear stress in the top 100 km of the subduction shear zone. Stress in Tonga is 220±100 bar, and in the Mariana it is 165±75 bar. These low stresses are probably made possible by a fluid pore pressure almost equal to the least compressive stress. Knowledge of stress allows approximate calculation of temperature in the shear zone by integration of a single differential equation. These temperatures are too low to activate most dehydration reactions in the subducted crust. As it approaches the volcanic line, this crust is at 150–350°C in Tonga and 150–300°C in the Mariana. Shear melting of the crust is ruled out, and conductive melting of the slab by contact with the asthenosphere meets with geochemical objections. Magmas in these systems are probably produced by partial melting of asthenosphere, triggered by a sudden release of water from the slab.

122 citations


Network Information
Related Topics (5)
Thermal conductivity
72.4K papers, 1.4M citations
78% related
Finite element method
178.6K papers, 3M citations
77% related
Nonlinear system
208.1K papers, 4M citations
76% related
Boundary value problem
145.3K papers, 2.7M citations
74% related
Turbulence
112.1K papers, 2.7M citations
74% related
Performance
Metrics
No. of papers in the topic in previous years
YearPapers
20242
20231,170
20222,180
2021774
20201,133
20191,317