Results 291 to 300 of about 2,145,711 (307)

Exploring 4D quantum Hall physics with a 2D topological charge pump

Nature, 2017
The discovery of topological states of matter has greatly improved our understanding of phase transitions in physical systems. Instead of being described by local order parameters, topological phases are described by global topological invariants and are
M. Lohse, C. Schweizer, H. Price, O. Zilberberg, I. Bloch   +4 more
semanticscholar   +1 more source

Modified Mach-Zehnder interferometer for determining the high-order topological charge of Laguerre-Gaussian vortex beams.

Journal of The Optical Society of America A-optics Image Science and Vision, 2019
This study demonstrates a self-referenced interferometric method to estimate the magnitude and sign of a high-order topological charge (TC) carried by incoming optical vortex beams.
Praveen Kumar, N. Nishchal
semanticscholar   +1 more source

Measuring the topological charge of optical vortices with a twisting phase.

Optics Letters, 2019
We analyzed the propagation characteristics of the intensity of a vortex beam after it passes through a twisting phase. It was found that the doughnut-like intensity pattern of a vortex beam would separate into several bright and dark fringes. The number
Donghui Shen, Daomu Zhao
semanticscholar   +1 more source

On topological excitations with isovector topological charges

Journal of Experimental and Theoretical Physics Letters, 1996
It is shown that degenerate systems with order parameter ψ taking on values in compact homogeneous subspaces TG or G/TG (where G is a simple compact group and TG is its maximum commutative subgroup) possess a rich collection of topological excitations (vortices or, correspondingly, instantons) with isovector topological charges.
openaire   +1 more source

Shaping optical beams with topological charge

Optics Letters, 2013
We show that by spatially arranging topological charges on a phase mask, it is possible to shape the spatial intensity profile of vortex beams in a controlled manner. As proof-of-principle experiments, we generated vortex beams with the spatial shape of straight lines, corners, and triangles.
Anderson M, Amaral, Edilson L, Falcão-Filho, Cid B, de Araújo   +2 more
openaire   +2 more sources

Gravitational topological charge

2008
In 1978 the procedure of application of the Inverse Scattering Method to General Relativity and of calculation of the exact solitonic solutions to the Einstein equations was described [1]. From that time not too much progress has been made in this field.
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The topological charge measurement of the vortex beam based on dislocation self-reference interferometry

Physica Scripta, 2019
Vortex beam generally refers to a kind of beam with orbital angular momentum, which has been widely implemented in the field of optical trapping, optical communication, rotation detection, etc.
Bin Lan, Chao Liu, Daoman Rui, Mo Chen, Feng Shen, H. Xian   +5 more
semanticscholar   +1 more source

Focus shaping of partially coherent radially polarized vortex beam with tunable topological charge.

Optics Express, 2019
In this paper, we have introduced a new class of partially coherent vector vortex beams, named radially polarized multi-Gaussian Schell-model (MGSM) vortex beam, carrying the vortex phase with tunable topological charges (i.e., both integral and ...
Hua-Feng Xu, R. Zhang, Z. Sheng, J. Qu
semanticscholar   +1 more source

Measuring the topological charge of an x-ray vortex using a triangular aperture

Journal of Optics, 2019
In this paper, for the first time, we demonstrate that the topological charge of a hard x-ray vortex can be measured by a single diffraction pattern from a triangular aperture.
Y. Taira, Y. Kohmura
semanticscholar   +1 more source

Beyond Standard Charge Density Topological Analyses

2011
The analysis and treatment of density matrices provides the decisive key for the understanding of molecular and solid state systems. The density matrices not only reflect the energetic state of the system as the whole, but also open a possibility for a decomposition of a system into parts accessible to our imagination and experience.
Pendás, A., Kohout, M., Blanco, M., Francisco, E.   +3 more
openaire   +2 more sources