Non-ergodic aging and hierarchical organization in lithium-potassium tantalate crystals
d'Acoustique et Optique de la Matière Condensée , Université P.
et M. Curie,
Case 78, 75252 Paris Cedex 05, France
Accepted: 3 January 1996
The dielectric constant of , with x = 0.01 and x = 0.025, and specially its value at very long times, measured as a function of time (aging) at 4 K, depends on the cooling rate; this is a non-ergodic behaviour which manifests the lack of self-similarity of the phase space. The response to temperature jumps, similar to that of spin-glasses, is the signature of hierarchical organization of the phase space. For x = 0 (pure ), the behaviour is ergodic.
PACS: 77.22.Gm – Dielectric loss and relaxation / 78.30.Ly – Disordered solids
© EDP Sciences, 1996