Посилання:Thermal conductivity of a quantum spin-1/2
antiferromagnetic chain with magnetic impurities / A.A. Zvyagin // Физика низких температур. — 2008. — Т. 34, № 3. — С. 273–277. — Бібліогр.: 15 назв. — англ.
Підтримка:The financial support from Deutsche Forschungsgemeinschaft (Grant No 436 UKR 17/21/06) is acknowledged. Stimulating discussions with B. Buchner, C. Hess,
S.-L. Drechsler, V. Kataev, and P. Ribeiro are greatly appreciated
We present an exact theory that describes how magnetic impurities change the behavior of the thermal
conductivity for the integrable Heisenberg antiferromagnetic quantum spin-1/2 chain. Single magnetic impurities
and a large concentration of impurities with similar values of the couplings to the host chain (a weak
disorder) do not change the linear-in-temperature low-T behavior of the thermal conductivity: Only the slope
of that behavior becomes smaller, comparing to the homogeneous case. The strong disorder in the distribution
of the impurity-host couplings produces more rapid temperature growth of the thermal conductivity,
compared to the linear in T dependence of the homogeneous chain and the chain with a weak disorder. Recent
experiments on the thermal conductivity in inhomogeneous quasi-one-dimensional quantum spin systems
manifest qualitative agreement with our results.