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Triple sign reversal of Hall effect in HgBa_{2}CaCu_{2}O_{6} thin films after heavy-ion irradiations

W. N. Kang·B. W. Kang·Q. Y. Chen·J. Z. Wu·Y. Bai·W. K. Chu·D. K. Christen·R. Kerchner·Sung-Ik Lee
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Abstract

Triple sign reversal in the mixed-state Hall effect has been observed for the first time in ion-irradiated HgBa_{2}CaCu_{2}O_{6} thin films. The negative dip at the third sign reversal is more pronounced for higher fields, which is opposite to the case of the first sign reversal near T_c in most high-T_c superconductors. These observations can be explained by a recent prediction in which the third sign reversal is attributed to the energy derivative of the density of states and to a temperature-dependent function related to the superconducting energy gap. These contributions prominently appear in cases where the mean free path is significantly decreased, such as our case of ion-irradiated thin films.

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W. N. Kang, B. W. Kang, Q. Y. Chen, J. Z. Wu, Y. Bai, W. K. Chu, D. K. Christen, R. Kerchner, Sung-Ik Lee. 1999-03-31. Triple sign reversal of Hall effect in HgBa_{2}CaCu_{2}O_{6} thin films after heavy-ion irradiations. https://doi.org/10.1103/physrevb.61.722

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