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arXiv · 0805.1363

Quantum Phase Transition in the Itinerant Antiferromagnet (V0.9Ti0.1)2O3

Hiroaki Kadowaki·Kiyoichiro Motoya·Taku J. Sato·J. W. Lynn·J. A. Fernandez-Baca·Jun Kikuchi
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Abstract

Quantum-critical behavior of the itinerant electron antiferromagnet (V0.9Ti0.1)2O3 has been studied by single-crystal neutron scattering. By directly observing antiferromagnetic spin fluctuations in the paramagnetic phase, we have shown that the characteristic energy depends on temperature as c_1 + c_2 T^{3/2}, where c_1 and c_2 are constants. This T^{3/2} dependence demonstrates that the present strongly correlated d-electron antiferromagnet clearly shows the criticality of the spin-density-wave quantum phase transition in three space dimensions.

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Hiroaki Kadowaki, Kiyoichiro Motoya, Taku J. Sato, J. W. Lynn, J. A. Fernandez-Baca, Jun Kikuchi. 2008-08-23. Quantum Phase Transition in the Itinerant Antiferromagnet (V0.9Ti0.1)2O3. https://doi.org/10.1103/physrevlett.101.096406

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