Magnon heat transport in (Sr,Ca,La)(14)Cu24O41

Article

关键词: PHONON THERMAL-CONDUCTIVITY;    SPIN GAP;    ANTIFERROMAGNETIC UNIFORM;    MAGNETIC EXCITATIONS;    CRYSTAL-GROWTH;    LADDERS;    THERMODYNAMICS;    INTERPLAY;    DYNAMICS;    SR2CUO3;   

DOI  :  10.1103/PhysRevB.64.184305

来源: SCIE

【 摘 要 】

We have measured the thermal heat conductivity kappa of the compounds Sr14Cu24O41 and Ca9La5Cu24O41 containing doped and undoped spin ladders, respectively. We find a huge anisotropy of both, the size and the temperature dependence of kappa that we interpret in terms of a very large heat conductivity due to the magnetic excitations of the one-dimensional spin ladders. This magnon heat conductivity decreases with increasing hole doping of the ladders. Magnon heat transport is analyzed theoretically using a simple kinetic model. From this analysis we determine the spin gap and the temperature-dependent mean free path of the magnons, which measures about several thousand angstrom at low temperature. The relevance of several scattering channels for the magnon transport is discussed.

【 授权许可】

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