Continuous quantum phase transition in a Kndo lattice model.
We study the magnetic quantum phase transition in an anisotropic Kondo lattice model. The dynamical competition between the RKKY and Kondo interactions is treated using an extended dynamic mean field theory appropriate for both the antiferromagnetic and paramagnetic phases. A quantum Monte Carlo approach is used, which is able to reach very low temperatures, of the order of 1% of the bare Kondo scale. We find that the finite-temperature magnetic transition, which occurs for sufficiently large RKKY interactions, is first order. The extrapolated zero-temperature magnetic transition, on the other hand, is continuous and locally critical.
Zhu
Jian-Xin
JX
Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
Grempel
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Qimiao
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