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Low-Temperature Hall Effect in Substituted Sr2RuO4

N. Kikugawa·A. P. Mackenzie·C. Bergemann·Y. Maeno
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Abstract

We report the results of a study of the Hall effect and magnetoresistance in single crystals of Sr2RuO4 in which Sr^(2+) has been substituted by La^(3+) (Sr(2-y)La(y)RuO(4)) or Ru^(4+) by Ti^(4+) (Sr(2)Ru(1-x)Ti(x)O(4)). For undoped Sr2RuO4, the purity is so high that the strong-field Hall coefficient can be measured for fields above 4 T. The conventional weak-field Hall coefficient as a function of doping shows a sharp jump and sign change at y ~ 0.01 that is unrelated to either a sharp change in Fermi-surface topography or a magnetic instability. The implications of these results are discussed.

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N. Kikugawa, A. P. Mackenzie, C. Bergemann, Y. Maeno. 2004-08-13. Low-Temperature Hall Effect in Substituted Sr2RuO4. https://doi.org/10.1103/physrevb.70.174501

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