发表机构
Yonsei University; Pohang University of Science and Technology; Hongik University（延世大学; 浦项科技大学; 弘益大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文提出有限动量声子无需手性或轴向性即可产生电子轨道角动量，建立规范场理论并推导标度律，为轨道电子学提供波矢可调的新途径。
AI 中文摘要
我们证明，即使没有声子的轴向性或手性，有限动量声子也能产生电子轨道角动量（OAM），该响应由声子波矢 $q$ 和频率 $\omega$ 控制。我们发展了一个普遍的规范场理论，其中幺正变换将声子位移吸收为作用于电子的涌现矢势和标量势，从而提供了OAM响应在 $q$ 和 $\omega$ 上的微扰分类。我们推导了交流和直流响应的 $q$ 和 $\omega$ 标度律。值得注意的是，即使对于线偏振声子，交流OAM也会出现，其大小和符号可通过 $q$ 调谐。其产生由声子几何与电子轨道纹理之间的匹配决定，而非仅由声子角动量决定。直流响应与电子贝里曲率的联系进一步支持声子角动量并非控制电子OAM产生的唯一自由度。在声学声子驱动下的含时紧束缚模拟独立证实了核心预测。我们的结果将声子驱动的OAM扩展到手性和轴向声子之外，并建立了一条波矢可调的轨道电子学路径，可通过表面声波实现。
英文摘要
We show that finite-momentum phonons generate electronic orbital angular momentum (OAM) even without phonon axiality or chirality, with the response controlled by the phonon wave vector $q$ and frequency $ω$. We develop a general gauge-field theory in which a unitary transformation absorbs the phonon displacement into emergent vector and scalar potentials acting on the electrons, providing a perturbative classification of the OAM response in $q$ and $ω$. We derive $q$- and $ω$-scaling laws for AC and DC responses. Notably, AC OAM arises even for linearly polarized phonons, with its magnitude and sign tunable by $q$. Its generation is governed by the matching between the phonon geometry and the electronic orbital texture rather than solely by the phonon angular momentum. The connection of the DC response to the electronic Berry curvature further supports that phonon angular momentum is not the only degree of freedom governing electronic OAM generation. Time-dependent tight-binding simulations under acoustic-phonon driving independently confirm the core predictions. Our results extend phonon-driven OAM beyond chiral and axial phonons and establish a wave-vector-tunable route to orbitronics, accessible with surface acoustic waves.
Comments8 pages, 5 figures
