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arXiv · 1304.6069

Structural and magnetic properties in the quantum S=1/2 dimer systems Ba3(Cr1-xVx)2O8 with site disorder

Tao Hong·L. Y. Zhu·X. Ke·V. O. Garlea·Y. Qiu·Y. Nambu·H. Yoshizawa·M. Zhu·G. E. Granroth·A. T. Savici·Zheng Gai·H. D. Zhou
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Abstract

We report a comprehensive study of dc susceptibility, specific heat, neutron diffraction, and inelastic neutron scattering measurements on polycrystalline Ba3(Cr1-xVx)2O8 samples, where x=0, 0.06, 0.15, and 0.53. A Jahn-Teller structure transition occurs for x=0, 0.06, and 0.15 samples and the transition temperature is reduced upon vanadium substitution from 70(2) K at x=0 to 60(2) K at x=0.06 and 0.15. The structure becomes less distorted as x increases and such transition disappears at x=0.53. The observed magnetic excitation spectrum indicates that the singlet ground state remains unaltered and spin gap energy \Delta=1.3(1) meV is identical within the instrument resolution for all x. In addition, the dispersion bandwidth W decreases with increase of x. At x=0.53, W is reduced to 1.4(1) meV from 2.0(1) meV at x=0.

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Tao Hong, L. Y. Zhu, X. Ke, V. O. Garlea, Y. Qiu, Y. Nambu, H. Yoshizawa, M. Zhu, G. E. Granroth, A. T. Savici, Zheng Gai, H. D. Zhou. 2013-04-22. Structural and magnetic properties in the quantum S=1/2 dimer systems Ba3(Cr1-xVx)2O8 with site disorder. https://doi.org/10.1103/physrevb.87.144427

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