All-electrical magnetisation switching via tilting spin propagation and polarization in MnTe spin source.

Crystallographic symmetry fundamentally governs the generation, propagation, and polarization of spin currents, which are the core processes in spin-orbit torque technology, yet harnessing this principle to realize field-free switching remains a critical challenge. Here, we propose a general symmetry-engineering strategy that tailors spin currents via tilting crystal axis. In epitaxial tilted MnTe (0001) thin films, all-electrical magnetization switching due to strong out-of-plane spin polarization was successfully observed, where spin propagation was reoriented. Remarkably, this approach yields an exceptionally high y-polarized spin-orbit torque efficiency (ξy = 0.58), together with a significant z-polarized component (ξz = 0.07). Our work proves crystal symmetry engineering as a powerful and versatile pathway for designing spin-source materials, opening new avenues for integrating high in-plane symmetry crystals into practical, energy-efficient spintronic devices.