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Updated: Jul 4, 2026

Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
Electron polarizability of crystalline solids in quantizing magnetic fields and topological gap numbers
Pavel Streda1, Thibaut Jonckheere, Thierry Martin
1Institute of Physics, Academy of Sciences of the Czech Republic, Cukrovarnická 10, 162 53 Praha, Czech Republic.
Abstract:
A theory of the static electron polarizability of crystals whose energy spectrum is modified by quantizing magnetic fields is presented. The polarizability is strongly affected by nondissipative Hall currents induced by the presence of crossed electric and magnetic fields: these can even change its sign. Results are illustrated in detail for a two-dimensional square lattice. The polarizability and the Hall conductivity are, respectively, linked to the two topological quantum numbers entering the so-called Diophantine equation. These numbers could in principle be detected in actual experiments.
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