Search

The angular-dependent magnetoresistance (AMR) of the ab plane is measured on the single crystals of iron-chalcogenide FeSe1–xSx (x = 0, 0.07, 0.13 and 1) and FeSe1–yTey (y = 0.06, 0.61 and 1) at various temperatures under fields up to 9 T. A pronounced twofold-anisotropic carrier-scattering effect is identified by AMR, and attributed to a magnetic-field-induced spin nematicity that emerges from the tetragonal normal-state regime below a characteristic temperature Tsn. This magnetically polarized spin nematicity is found to be ubiquitous in the isoelectronic FeSe1–xSx and FeSe1–yTey systems, no matter whether the sample shows an electronic nematic order at Ts ≲ Tsn, or an antiferromagnetic order at TN < Tsn, or neither order. Importantly, we find that the induced spin nematicity shows a very different response to sulfur substitution from the spontaneous electronic nematicity: The spin-nematic Tsn is not suppressed but even enhanced by the substitution, whereas the electronic-nematic Ts is rapidly suppressed, in the FeSe1–xSx system. Furthermore, we find that the superconductivity is significantly suppressed with the enhancement of the induced spin nematicity in both FeSe1–xSx and FeSe1–yTey samples. [ABSTRACT FROM AUTHOR]