Se p 19 99 Memory and chaos in the aging of a polymer glass
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چکیده
Low frequency dielectric measurements on plexiglass (PMMA) show that cooling and heating the sample at constant rate give an hysteretic dependence on temperature of the dielectric constant ǫ. A temporary stop of cooling produces a downward relaxation of ǫ. Two main features are observed i) when cooling is resumed ǫ goes back to the values obtained without the cooling stop (Chaos, i.e. the low temperature state is independent of the cooling history) ii) upon reheating ǫ reminds the aging history (Memory). The analogies and differences with similar experiments done in spin glasses are discussed.
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تاریخ انتشار 2008