The spin Hall effect (SHE) is usually observed as a bulk effect in high-symmetry crystals with substantial spin–orbit coupling (SOC), where the symmetric spin–orbit field imposes a widely encountered trade-off between spin Hall angle (θ_SH) and spin diffusion length (L_sf), and spin polarization, spin current and charge current are constrained to be mutually orthogonal. Here, we report a large θ_SH of 0.32 accompanied by a long L_sf of 2.2 μm at room temperature in a low-symmetry few-layered semimetal MoTe₂, thus identifying it as an excellent candidate for simultaneous spin generation, transport and detection. In addition, we report that longitudinal spin current with out-of-plane polarization can be generated by both transverse and vertical charge current, due to the conventional and a newly observed planar SHE, respectively. Our study suggests that manipulation of crystalline symmetries and strong SOC opens access to new charge-spin interconversion configurations and spin–orbit torques for spintronic applications.

自旋霍尔效应 (SHE) 通常在具有大量自旋轨道耦合 (SOC) 的高对称晶体中被观察为体效应，其中对称自旋轨道场在自旋霍尔角 ( θ _SH ) 和自旋扩散长度 ( L _sf )，并且自旋极化、自旋电流和充电电流被约束为相互正交。在这里，我们报告了在室温下在低对称少层半金属 MoTe _{2中具有 0.32 的大}θ _SH和 2.2 μm的长L _sf，因此将其确定为同时自旋生成、传输和检测的优秀候选者。此外，我们报告了具有平面外极化的纵向自旋电流可以由横向和垂直充电电流产生，这分别是由于常规和新观察到的平面 SHE。我们的研究表明，对晶体对称性和强 SOC 的操纵为自旋电子应用开辟了获得新的电荷-自旋互变配置和自旋轨道扭矩的途径。