Dielectric constant of glasses: first observation of a two-dimensional behavior

F. Ladieu; J. Le Cochec; P. Pari; P. Trouslard; P. Ailloud

doi:10.1103/physrevlett.90.205501

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Dielectric constant of glasses: first observation of a two-dimensional behavior

F. Ladieu·J. Le Cochec·P. Pari·P. Trouslard·P. Ailloud

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Abstract

The 1kHz real part $χ'$ of the dielectric constant of a structural glass was measured at low temperature $T$ down to 14 mK. Reducing the sample thickness $h$ to 10 nm suppresses the usual minimum of $χ'$ for measuring fields $E<.5 $ MV/m. This contradicts the Two Level System (TLS) model but is well accounted for by including TLS-TLS interactions where excitations delocalize between TLS's through a $E$-induced mechanism recently designed: for small $h$'s this interaction is reduced, which explains the two-dimensional behavior of $χ'(T)$. Hence, interactions play a key role in standard thick samples.

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F. Ladieu, J. Le Cochec, P. Pari, P. Trouslard, P. Ailloud. 2002-10-01. Dielectric constant of glasses: first observation of a two-dimensional behavior. https://doi.org/10.1103/physrevlett.90.205501

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