II. Physikalisches Institut, Universität zu Köln, Zülpicher Str. 77, D-50937 Köln, Germany.
Institut Laue Langevin, 71 avenue des Martyrs, 38000 Grenoble, France.
Phys Rev Lett. 2019 Feb 1;122(4):047004. doi: 10.1103/PhysRevLett.122.047004.
Triplet pairing in Sr_{2}RuO_{4} was initially suggested based on the hypothesis of strong ferromagnetic spin fluctuations. Using polarized inelastic neutron scattering, we accurately determine the full spectrum of spin fluctuations in Sr_{2}RuO_{4}. Besides the well-studied incommensurate magnetic fluctuations, we do find a sizable quasiferromagnetic signal, quantitatively consistent with all macroscopic and microscopic probes. We use this result to address the possibility of magnetically driven triplet superconductivity in Sr_{2}RuO_{4}. We conclude that, even though the quasiferromagnetic signal is stronger and sharper than previously anticipated, spin fluctuations alone are not enough to generate a triplet state strengthening the need for additional interactions or an alternative pairing scenario.
Sr_{2}RuO_{4}中的三重态配对最初是基于强铁磁自旋涨落的假设提出的。利用极化非弹性中子散射，我们准确地确定了 Sr_{2}RuO_{4}中自旋涨落的全谱。除了研究充分的非晶磁性波动外，我们确实发现了相当大的准铁磁信号，与所有宏观和微观探针定量一致。我们利用这一结果来探讨 Sr_{2}RuO_{4}中磁驱动三重态超导的可能性。我们的结论是，尽管准铁磁信号比先前预期的更强、更尖锐，但仅凭自旋涨落不足以产生一个加强三重态的状态，这需要额外的相互作用或替代配对方案。
