有限温度下d波交替磁体中的涌现斯格明子霍尔效应
Emergent Skyrmion Hall Effect in $d$-wave Altermagnets at Finite Temperature
AI总结：
该研究发现有限温度下d波交替磁体中会涌现各向异性斯格明子霍尔效应，可通过电压控制实现ATM斯格明子的低功耗输运调控。
AI中文摘要：
交替磁体（Altermagnets）兼具补偿型磁序与非常规的对称性依赖响应，为自旋电子学应用提供了极具潜力的平台。本文研究表明，在无热涨落的情况下，电压控制的磁各向异性梯度会驱动交替磁体（ATM）斯格明子以近乎直线、无霍尔效应的方式运动，这源于其高度补偿的旋光响应。热磁子会通过磁子-斯格明子散射增加纵向拖拽力，并通过手征依赖的偏散射产生横向反作用力，从而定性改变上述行为。由于交替磁体的磁子能带结构具有各向异性，两种磁子手征的相对传输权重在沿x方向与y方向传播时会发生互换，进而产生符号相反的横向斯格明子漂移。相比之下，沿高对称方向时，两种磁子手征保持简并，其横向贡献相互抵消，即便在有限温度下仍能保持无霍尔效应的运动。我们由此揭示了一种热涌现的各向异性斯格明子霍尔效应，其方向依赖的大小与符号源于本征的对称性依赖磁子谱，是ATM斯格明子在有限温度下的通用动力学特征。本研究为实现电控、热可调的ATM斯格明子输运开辟了低功耗路径。
英文摘要：
Altermagnets combine compensated magnetic order with unconventional symmetry-dependent responses, offering a promising platform for spintronic applications. Here, we show that a voltage-controlled magnetic-anisotropy gradient drives altermagnetic (ATM) skyrmions in a nearly rectilinear, Hall-free manner in the absence of thermal fluctuations, owing to their strongly compensated gyrotropic response. Thermal magnons qualitatively modify this behavior by increasing the longitudinal drag through magnon--skyrmion scattering and generating a transverse reaction force through handedness-dependent skew scattering. Owing to the anisotropic altermagnetic magnon band structure, the relative transport weights of the two magnon handednesses are interchanged between propagation along the $x$ and $y$ directions, resulting in transverse skyrmion drifts of opposite sign. By contrast, along the high-symmetry direction, the two magnon handednesses remain degenerate and their transverse contributions cancel, preserving Hall-free motion even at finite temperature. We thus uncover a thermally emergent anisotropic skyrmion Hall effect whose direction-dependent magnitude and sign originate from the intrinsic symmetry-dependent magnon spectrum, making it a generic finite-temperature dynamical feature of ATM skyrmions. Our results establish a low-power route toward electrically controlled and thermally tunable ATM skyrmion transport.
