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Spin-Orbital Fluctuations and a large mass enhancement in LiV_2O_4

Yasufumi Yamashita·Kazuo Ueda
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Abstract

We present a scenario that the multi-component fluctuations, especially those of the spin-orbital coupled modes, lead to the mass enhancement observed in LiV_2O_4. This phenomena is possible because all these modes are fluctuating due to the geometrical frustration. To illustrate this mechanism, the t_{2g}-orbital Hubbard model on the pyrochlore lattice is studied based on the random-phase approximation. We derive the generalized susceptibility in the SU(6) spin-orbital space and calculate the free energy by using a coupling-constant integration. The estimated specific heat coefficient is of the correct order of magnitude to explain the experiment.

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Yasufumi Yamashita, Kazuo Ueda. 2002-12-06. Spin-Orbital Fluctuations and a large mass enhancement in LiV_2O_4. https://doi.org/10.1103/physrevb.67.195107

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