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Interpretation of the angular dependence of the de Haas-van Alphen effect in MgB_2

A. Carrington·J. D. Fletcher·H. Harima
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Abstract

We present detailed results for the amplitude and field dependence of the de Haas-van Alphen (dHvA) signal arising from the electron-like $π$ sheet of Fermi surface in MgB_2. Our data and analysis show that the dip in dHvA amplitude when the field is close to the basal plane is caused by a beat between two very similar dHvA frequencies and not a spin-zero effect as previously assumed. Our results imply that the Stoner enhancement factors in MgB_2 are small on both the Sigma and Pi sheets.

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A. Carrington, J. D. Fletcher, H. Harima. 2004-12-14. Interpretation of the angular dependence of the de Haas-van Alphen effect in MgB_2. https://doi.org/10.1103/physrevb.71.174505

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