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arXiv · 0708.2069

Relativistic analysis of magnetoelectric crystals: extracting a new 4-dimensional P odd and T odd pseudoscalar from Cr_2 O_3 data

Friedrich W. Hehl·Yuri N. Obukhov·Jean-Pierre Rivera·Hans Schmid
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Abstract

Earlier, the linear magnetoelectric effect of chromium sesquioxide Cr_2 O_3 has been determined experimentally as a function of temperature. One measures the electric field-induced magnetization on Cr_2 O_3 crystals or the magnetic field-induced polarization. From the magnetoelectric moduli of Cr_2 O_3 we extract a 4-dimensional relativistic invariant pseudoscalar \tildeα. It is temperature dependent and of the order of ~ 10^{-4} Y_0, with Y_0 as vacuum admittance. We show that the new pseudoscalar \tildeαis odd under parity transformation and odd under time inversion. Moreover, \tildeαis for Cr_2 O_3 what Tellegen's gyrator is for two port theory, the axion field for axion electrodynamics, and the PEMC (perfect electromagnetic conductor) for electrical engineering.

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Friedrich W. Hehl, Yuri N. Obukhov, Jean-Pierre Rivera, Hans Schmid. 2007-08-15. Relativistic analysis of magnetoelectric crystals: extracting a new 4-dimensional P odd and T odd pseudoscalar from Cr_2 O_3 data. https://doi.org/10.1016/j.physleta.2007.08.069

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