Sharp magnetization jump at the first-order superconducting transition in Sr2RuO4

Article

关键词: PT-195 KNIGHT-SHIFT;    UPT3;   

DOI  :  10.1103/PhysRevB.90.220502

来源: SCIE

【 摘 要 】

The magnetization and magnetic torque of a high-quality single crystal of Sr2RuO4 have been measured down to 0.1 K under precise control of the magnetic-field orientation. When the magnetic field is applied exactly parallel to the ab plane, a sharp magnetization jump 4 pi delta M of (0.74 +/- 0.15) G at the upper critical field H-c2,H-ab similar to 15 kOe with a field hysteresis of 100 Oe is observed at low temperatures, evidencing a first-order superconducting-normal transition. A strong magnetic torque appearing when H is slightly tilted away from the ab plane confirms an intrinsic anisotropy Gamma = xi(a)/xi(c) of as large as 60 even at 100 mK, in contrast with the observed H-c2 anisotropy of similar to 20. The present results raise fundamental issues in both the existing spin-triplet and spin-singlet scenarios, providing, in turn, crucial hints toward the resolution of the superconducting nature of Sr2RuO4.

【 授权许可】

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