The interplay between spin–orbit coupling and structural inversion symmetry breaking in solids has generated much interest due to the nontrivial spin and magnetic textures which can result. Such studies are typically focused on systems where large atomic number elements lead to strong spin–orbit coupling, in turn rendering electronic correlations weak. In contrast, here we investigate the temperature-dependent electronic structure of Ca3Ru2O7, a 4d oxide metal for which both correlations and spin–orbit coupling are pronounced and in which octahedral tilts and rotations combine to mediate both global and local inversion symmetry-breaking polar distortions. Our angle-resolved photoemission measurements reveal the destruction of a large hole-like Fermi surface upon cooling through a coupled structural and spin-reorientation transition at 48 K, accompanied by a sudden onset of quasiparticle coherence. We demonstrate how these result from band hybridization mediated by a hidden Rashba-type spin–orbit coupling. This is enabled by the bulk structural distortions and unlocked when the spin reorients perpendicular to the local symmetry-breaking potential at the Ru sites. We argue that the electronic energy gain associated with the band hybridization is actually the key driver for the phase transition, reflecting a delicate interplay between spin–orbit coupling and strong electronic correlations and revealing a route to control magnetic ordering in solids.

由于自旋和磁织构的不平凡，自旋-轨道耦合与固体中结构反转对称破裂之间的相互作用引起了人们极大的兴趣。这样的研究通常集中在大原子序数元素导致强烈的自旋-轨道耦合，从而使电子相关性弱的系统上。相比之下，在这里我们研究与温度有关的电子结构C一种3[Rü2Ø7， 一种 4d这种氧化物金属具有明显的相关性和自旋-轨道耦合，并且八面体的倾斜和旋转结合起来可以介导整体和局部反转对称性破坏性极地畸变。我们的角度分辨光发射测量结果显示，在48 K处通过耦合的结构和自旋取向转变进行冷却后，大孔状费米表面的破坏，伴随着准粒子相干的突然出现。我们证明了这些是如何由隐藏的Rashba型自旋轨道耦合介导的带杂交产生的。这可以通过整体结构变形来实现，并在自旋垂直于Ru位置处的局部对称破坏势垂直时重新定向。