Magnetic field effect on the dielectric constant of glasses: Evidence of disorder within tunneling barriers

J Le Cochec (1, 2) , F Ladieu (2, 1) , P Pari (1)

1 SPEC - UMR3680 - Service de physique de l'état condensé
2 LPS - Laboratoire Pierre Süe

The magnetic field dependence of the low frequency dielectric constant ǫr(H) of a structural glass a − SiO2+xCyHz was studied from 400 mK to 50 mK and for H up to 3 T. Measurement of both the real and the imaginary parts of ǫr is used to eliminate the difficult question of keeping constant the temperature of the sample while increasing H: a non-zero ǫr(H) dependence is reported in the same range as that one very recently reported on multicomponent glasses. In addition to the recently proposed explanation based on interactions, the reported ǫr(H) is interpreted quantitatively as a consequence of the disorder lying within the nanometric barriers of the elementary tunneling systems of the glass.

Mots clés: numbers: 6143Fs; 7722Gm; 7220Ht; 7220My

Domaines: Physique [physics]

J Le Cochec, F Ladieu, P Pari. Magnetic field effect on the dielectric constant of glasses: Evidence of disorder within tunneling barriers. Physical Review B: Condensed Matter and Materials Physics (1998-2015), 2002, 66, ⟨10.1103/PhysRevB.66.064203⟩. ⟨cea-01395460⟩