发表机构
Institute for Materials Research, Tohoku University（东北大学物质材料研究研究所）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究从扩展哈伯德模型推导有效赝自旋模型，揭示电荷有序可映射为交错赝自旋序，外电场可驱动电荷有序极性相干翻转，为电荷有序调控提供了新微观框架。
AI 中文摘要
电荷有序通常被视为电子密度的静态调制，尽管探测和操控其非平衡演化的实验能力正在不断提升。与自旋有序系统相比，电荷有序动力学及其在外场驱动下的调控的微观框架仍未充分发展。本文从扩展哈伯德模型出发，推导得到一个有效赝自旋模型，其中电荷有序态映射为交错赝自旋序。所得电荷有序动力学由类似朗道-利夫希茨-吉尔伯特方程的赝自旋方程描述，与二分反铁磁体的情况极为相似。研究表明，外电场可直接调控交错赝自旋序，且在阈值电场以上，通过破坏集体赝自旋激发的稳定性，可驱动电荷有序极性的相干翻转。本研究确立了电荷赝自旋作为电荷有序相干切换与调控的微观动力学自由度，为自旋电子学中已成熟的自旋有序动力学框架提供了电荷领域的类似物。
英文摘要
Charge order is conventionally viewed as a static modulation of the electronic density, despite growing experimental capabilities to probe and manipulate its nonequilibrium evolution. In contrast to spin-ordered systems, a microscopic framework for charge-order dynamics and its control under external driving remains largely underdeveloped. Here, starting from an extended Hubbard model, we derive an effective pseudospin model in which the charge-ordered state maps onto staggered pseudospin order. The resulting charge-order dynamics is governed by Landau--Lifshitz--Gilbert-like equations for the pseudospins, closely analogous to those of a bipartite antiferromagnet. We show that an external electric field directly controls the staggered pseudospin order and, above a threshold field, drives coherent reversal of the charge-order polarity by destabilizing collective pseudospin excitations. Our results establish the charge pseudospin as a microscopic dynamical degree of freedom for coherent switching and control of charge order, providing a charge-sector analogue of the well-established framework for spin-order dynamics in spintronics.
