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Updated: Jun 3, 2026

Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
A phenomenological Landau theory for electromagnons in cubic spinel multiferroic CoCr₂O₄
1Banaras Hindu University, Varanasi-221005, India.
Abstract:
Non-anisotropic free energy is considered which under minimization yields two magnetic phases: a conical spin density wave and a low temperature conical cycloid. Using equations of motion, the excitation spectrum is studied. Knowing the nature of these excitations, the dielectric function as well as the fluctuation specific heat is computed and compared with the experimental spectrum. Due to the electromagnon going soft, the dielectric function (imaginary part) as well as the specific heat capacity show peaks at the temperature where ferroelectricity appears in the system.
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