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Persistent spin texture (PST) describes a unique spin‐momentum locking in momentum space that maintains a uniform spin orientation through portions of the Brillouin zone (BZ), enabling exceptionally long spin lifetimes, which are essential for applications in spintronics. However, materials exhibiting large BZ regions of high‐quality PST, characterized by minimal spin deviation and long spin lifetimes, remain scarce. Here, a universal model is introduced to capture the formation of superior PST regions arising from the interplay of spin–orbit fields at differentkpoints. Within this framework, high‐quality PSTs are identified in several systems belonging to various point groups. Notably, the nonpolar‐chiral compound Na₂Sn₂O₃exhibits a 0.02 Å⁻²high‐quality PST region, which can be reversed by the switching of geometric chirality, while AgClO₄(D_2dsymmetry) exhibits a 0.016 Å⁻²PST region. Significantly, Na₂Sn₂O₃and AgClO₄are predicted to host persistent spin helices with spin lifetimes of 0.5–7.4 and 0.9–2.5 ns, respectively, among the longest reported for PST materials. In addition, both chemical substitution and the application of pressure are demonstrated as effective routes for engineering high‐quality PST. Our findings not only establish a universal principle for high‐quality PST, but also provide promising materials across various point groups for the next‐generation spintronic devices. 

Abstract Dielectrics have long been considered as unsuitable for pure electrical switches; under weak electric fields, they show extremely low conductivity, whereas under strong fields, they suffer from irreversible damage. Here, we show that flexoelectricity enables damage-free exposure of dielectrics to strong electric fields, leading to reversible switching between electrical states—insulating and conducting. Applying strain gradients with an atomic force microscope tip polarizes an ultrathin film of an archetypal dielectric SrTiO 3 via flexoelectricity, which in turn generates non-destructive, strong electrostatic fields. When the applied strain gradient exceeds a certain value, SrTiO 3 suddenly becomes highly conductive, yielding at least around a 10 8 -fold decrease in room-temperature resistivity. We explain this phenomenon, which we call the colossal flexoresistance, based on the abrupt increase in the tunneling conductance of ultrathin SrTiO 3 under strain gradients. Our work extends the scope of electrical control in solids, and inspires further exploration of dielectric responses to strong electromechanical fields.