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Spin Waves in Random Spin Chains

Xin Wan·Kun Yang·Chenggang Zhou·R. N. Bhatt
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Abstract

We study quantum spin-1/2 Heisenberg ferromagnetic chains with dilute, random antiferromagnetic impurity bonds with modified spin-wave theory. By describing thermal excitations in the language of spin waves, we successfully observe a low-temperature Curie susceptibility due to formation of large spin clusters first predicted by the real-space renormalization-group approach, as well as a crossover to a pure ferromagnetic spin chain behavior at intermediate and high temperatures. We compare our results of the modified spin-wave theory to quantum Monte Carlo simulations.

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Xin Wan, Kun Yang, Chenggang Zhou, R. N. Bhatt. 2002-08-30. Spin Waves in Random Spin Chains. https://doi.org/10.1063/1.1541640

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