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arXiv · 1208.2227

Nonlinear dielectric response at the excess wing of glass-forming liquids

Th. Bauer·P. Lunkenheimer·S. Kastner·A. Loidl
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Abstract

We present nonlinear dielectric measurements of glass-forming glycerol and propylene carbonate applying electrical fields up to 671 kV/cm. The measurements extend to sufficiently high frequencies to allow for the investigation of the nonlinear behavior in the regime of the so-far mysterious excess wing, showing up in the loss spectra of many glass formers as a second power law at high frequencies. Surprisingly, we find a complete lack of nonlinear behavior in the excess wing, in marked contrast to the alpha-relaxation where, in agreement with previous reports, a strong increase of dielectric constant and loss is found.

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Th. Bauer, P. Lunkenheimer, S. Kastner, A. Loidl. 2012-08-10. Nonlinear dielectric response at the excess wing of glass-forming liquids. https://doi.org/10.1103/physrevlett.110.107603

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