L lines, C points and Chern numbers: understanding band structure topology using polarization fields

Autor: Thomas Fösel, Vittorio Peano, Florian Marquardt
Jazyk: angličtina
Rok vydání: 2017
Předmět:
Zdroj: New Journal of Physics, Vol 19, Iss 11, p 115013 (2017)
Druh dokumentu: article
ISSN: 1367-2630
DOI: 10.1088/1367-2630/aa8a9f
Popis: Topology has appeared in different physical contexts. The most prominent application is topologically protected edge transport in condensed matter physics. The Chern number, the topological invariant of gapped Bloch Hamiltonians, is an important quantity in this field. Another example of topology, in polarization physics, are polarization singularities, called L lines and C points. By establishing a connection between these two theories, we develop a novel technique to visualize and potentially measure the Chern number: it can be expressed either as the winding of the polarization azimuth along L lines in reciprocal space, or in terms of the handedness and the index of the C points. For mechanical systems, this is directly connected to the visible motion patterns.
Databáze: Directory of Open Access Journals