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Thermal Entanglement in Ferrimagnetic Chains

Xiaoguang Wang·Z. D. Wang
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Abstract

A formula to evaluate the entanglement in an one-dimensional ferrimagnetic system is derived. Based on the formula, we find that the thermal entanglement in a small size spin-1/2 and spin-s ferrimagnetic chain is rather robust against temperature, and the threshold temperature may be arbitrarily high when s is sufficiently large. This intriguing result answers unambiguously a fundamental question: ``can entanglement and quantum behavior in physical systems survive at arbitrary high temperatures?"

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Xiaoguang Wang, Z. D. Wang. 2006-04-13. Thermal Entanglement in Ferrimagnetic Chains. https://doi.org/10.1103/physreva.73.064302

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