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Coexisting Kondo singlet state with antiferromagnetic long-range order: A possible ground state for Kondo insulators

Guang-Ming Zhang·Lu Yu
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Abstract

The ground-state phase diagram of a half-filled anisotropic Kondo lattice model is calculated within a mean-field theory. For small transverse exchange coupling $J_{\perp} J_{\perp c2}$, the long-range order is destroyed and the system is in a disordered Kondo singlet state with a hybridization gap. Both ground states can describe the low-temperature phases of Kondo insulating compounds. Between these two distinct phases, there may be a coexistent regime as a result of the balance between local Kondo screening and magnetic interactions.

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Guang-Ming Zhang, Lu Yu. 2000-04-29. Coexisting Kondo singlet state with antiferromagnetic long-range order: A possible ground state for Kondo insulators. https://doi.org/10.1103/physrevb.62.76

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