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Spin-zero anomaly in the magnetic quantum oscillations of a two-dimensional metal

J. Wosnitza·V. M. Gvozdikov·J. Hagel·P. J. Meeson·J. A. Schlueter·R. W. Winter·G. L. Gard
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Abstract

We report on an anomalous behavior of the spin-splitting zeros in the de Haas-van Alphen (dHvA) signal of a quasi-two-dimensional organic superconductor. The zeros as well as the angular dependence of the amplitude of the second harmonic deviate remarkably from the standard Lifshitz-Kosevich (LK) prediction. In contrast, the angular dependence of the fundamental dHvA amplitude as well as the spin-splitting zeros of the Shubnikov-de Haas signal follow the LK theory. We can explain this behavior by small chemical-potential oscillations and find a very good agreement between theory and experiment. A detailed wave-shape analysis of the dHvA signal corroborates the existence of an oscillating chemical potential.

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J. Wosnitza, V. M. Gvozdikov, J. Hagel, P. J. Meeson, J. A. Schlueter, R. W. Winter, G. L. Gard. 2004-12-08. Spin-zero anomaly in the magnetic quantum oscillations of a two-dimensional metal. https://doi.org/10.1088/1367-2630%2F10%2F8%2F083032

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