Electron carriers with possible Dirac-cone-like dispersion in FeSe1-xSx (x=0 and 0.14) single crystals triggered by structural transition

Article

关键词: SUPERCONDUCTIVITY;    FESE;    MAGNETORESISTANCE;    PHASE;   

DOI  :  10.1103/PhysRevB.93.104502

来源: SCIE

【 摘 要 】

We report detailed study of the transport properties of FeSe1-xSx (x = 0 and 0.14) single crystals grown by vapor transport method. 14% S doping is found to significantly suppress the structural transition from T-s similar to 86 K in FeSe to similar to 49 K, although the superconducting transition temperature T-c is only slightly affected. A pronounced linear magnetoresistance (MR) is observed in both FeSe and FeSe0.86S0.14 single crystals, which is found to be triggered by the structural transition. The linear MR and related discussion indicate the possible existence of Dirac-cone-like state, which may come from the band shift induced by ferro-orbital order. The mobility of the Dirac-cone-like band is found to decrease after S doping. Besides, the invalid Kohler's scaling of MR is found for temperature below Ts in both crystals, however, the reestablishment of the Kohler's scaling at temperatures below 30 K is observed in FeSe, but not in FeSe0.86S0.14. All these observations above support that the orbital ordering causes the band reconstruction in FeSe, and also that the orbital ordering in FeSe is suppressed by the chemical pressure from S doping.

【 授权许可】

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