论文标题
SR2RUO4中的水平线节点通过自旋共振证明
Horizontal Line Nodes in Sr2RuO4 Proved by Spin Resonance
论文作者
论文摘要
我们通过高分辨率非弹性中子中子散射测量和随机相位近似（RPA）计算研究了SR $ _2 $ ruo $ _4 $中低能不良（IC）的磁波。我们观察到了$ \hbarΩ_\ text {res} = 0.56 $ 〜MEV的旋转共振，以特征性wavevector $ \ mathbf {q} _ \ text {res} =（0.3，0.3，0.3，0.5）$。共振能很好地对应于超导间隙$2δ= 0.56 $ 〜MEV由隧道光谱估计。自旋共振显示了$ L $调制，最大值约为$ L = 0.5 $。 $ l $调制的旋转共振强度和我们的RPA计算表明，在费米表面上有关准二维$α$和$β$ sheets的超导差距具有水平线节点。这些结果可能会对SR $ _2 $ ruo $ _4 $的配对对称性产生强大的限制。我们还讨论了对可能的超导顺序参数的影响。
We investigated the low-energy incommensurate (IC) magnetic fluctuations in Sr$_2$RuO$_4$ by the high-resolution inelastic neutron scattering measurements and random phase approximation (RPA) calculations. We observed a spin resonance with energy of $\hbarω_\text{res}=0.56$~meV centered at a characteristic wavevector $\mathbf{Q}_\text{res}=(0.3, 0.3, 0.5)$. The resonance energy corresponds well to the superconducting gap $2Δ=0.56$~meV estimated by the tunneling spectroscopy. The spin resonance shows the $L$ modulation with a maximum at around $L = 0.5$. The $L$ modulated intensity of the spin resonance and our RPA calculations indicate that the superconducting gaps regarding the quasi-one-dimensional $α$ and $β$ sheets at the Fermi surfaces have the horizontal line nodes. These results may set a strong constraint on the pairing symmetry of Sr$_2$RuO$_4$. We also discuss the implications on possible superconducting order parameters.
