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Microscopic Magnetic Properties of (V$_{1-x}$Ti$_{x}$)$_2$O$_3$ near the Phase Boundary of the Metal-Insulator Transition

Jun Kikuchi·Noriyuki Wada·Kousuke Nara·Kiyoichiro Motoya
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Abstract

Magnetic susceptibility (chi) and $^{51}$V NMR have been measured in (V$_{1-x}$Ti$_{x}$)$_2$O$_3$ near the phase boundary of the metal-insulator transition. It is established that the transition from antiferromagnetic insulating (AFI) to antiferromagnetic metallic phases near $x_{\rm c}\approx 0.05$ is not quantum critical but is discontinuous with a jump of the transition temperature. In the AFI phase at 4.2 K, we observed the satellite in the zero-field $^{51}$V NMR spectrum around 181 MHz in addition to the ``host'' resonance around 203 MHz. The satellite is also observable in the paramagnetic metallic phase of the x = 0.055 sample. We associated the satellite with the V sites near Ti which are in the V$^{3+}$-like oxidation state but has different temperature dependence of the NMR shift from that of the host V site. The host d-spin susceptibility for x = 0.055 decreases below $\sim$60 K but remains finite in the low-temperature limit.

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Jun Kikuchi, Noriyuki Wada, Kousuke Nara, Kiyoichiro Motoya. 2001-12-01. Microscopic Magnetic Properties of (V$_{1-x}$Ti$_{x}$)$_2$O$_3$ near the Phase Boundary of the Metal-Insulator Transition. https://doi.org/10.1016/s0022-3697(02)00016-1

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