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Anomalous thermal conductivity and local temperature distribution on harmonic Fibonacci chains

Masashi Torikai·Takashi Odagaki
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Abstract

The harmonic Fibonacci chain, which is one of a quasiperiodic chain constructed with a recursion relation, has a singular continuous frequency-spectrum and critical eigenstates. The validity of the Fourier law is examined for the harmonic Fibonacci chain with stochastic heat baths at both ends by investigating the system size N dependence of the heat current J and the local temperature distribution. It is shown that J asymptotically behaves as (ln N)^{-1} and the local temperature strongly oscillates along the chain. These results indicate that the Fourier law does not hold on the harmonic Fibonacci chain. Furthermore the local temperature exhibits two different distribution according to the generation of the Fibonacci chain, i.e., the local temperature distribution does not have a definite form in the thermodynamic limit. The relations between N-dependence of J and the frequency-spectrum, and between the local temperature and critical eigenstates are discussed.

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Masashi Torikai, Takashi Odagaki. 2002-04-22. Anomalous thermal conductivity and local temperature distribution on harmonic Fibonacci chains. https://doi.org/10.1088/0953-8984%2F14%2F26%2F103

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