发表机构
National Laboratory of the Rockies（落基山国家实验室）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究提出统一规则证明手性诱导自旋选择性（CISS）是非平衡效应，通过多层级输运验证，揭示手性振动产生极化并受自旋轨道耦合调控，为竞争机制提供统一检验。
AI 中文摘要
二十年来，手性诱导自旋选择性（CISS）的起源——即无磁场条件下非磁性手性系统对电子的自旋极化——一直悬而未决。在此，我们建立了一条精确的单一规则，用以定义该效应的基本条件：在非磁性、时间反演不变的导体中，所有可测量的CISS信号都是时间反演奇的，并且在接近平衡时消失，这证明单纯的结构手性是不够的。通过评估四个非平衡输运层级上的主要理论机制，从相干经典驱动到完全非马尔可夫量子浴，我们以机器精度验证了这一选择规则。我们表明，相干手性振动会产生显著的共线极化（在0.5-6 THz范围内高达10%），且随手性反转而反向，而非相干振动产生的极化低于1%，非马尔可夫浴记忆进一步抑制了该信号。手性几何首先通过累积轨道角动量使电子运动变得手性；随后自旋-轨道耦合（SOC）将其转化为自旋。因此，CISS既充当自旋极化器又充当自旋过滤器，后者的强度低一个数量级。极化随分子长度增长然后饱和，这与DNA和多肽中报道的趋势一致。反转驱动将衰减的自旋转换为手性锁定的电荷电流脉冲（逆CISS）。我们发现，一旦系统被驱动，极化幅度与有效自旋-轨道耦合成正比：在等效有效SOC下，重原子和弯曲的轻原子骨架变得难以区分。这使我们能够描绘几何、驱动场和长度如何区分这些路径。
英文摘要
For two decades, the origin of Chirality-Induced Spin Selectivity (CISS), the spin polarization of electrons by nonmagnetic chiral systems without magnetic fields, has remained unsettled. Here, we establish a single exact rule defining the fundamental conditions for the effect: in nonmagnetic, time-reversal-invariant conductors, all measurable CISS signals are time-reversal odd and vanish near equilibrium, proving that structural chirality alone is insufficient. By evaluating leading theoretical mechanisms across four levels of nonequilibrium transport, from coherent classical driving to fully non-Markovian quantum baths, we verify this selection rule to machine precision. We show that coherent chiral vibrations generate substantial collinear polarization (up to 10 percent across 0.5-6 THz) that reverses with handedness, whereas incoherent vibrations yield under 1 percent, and non-Markovian bath memory further suppresses the signal. The chiral geometry first makes the electronic motion chiral by accumulating orbital angular momentum; spin-orbit coupling (SOC) then converts that into spin. CISS therefore acts as both a spin polarizer and a spin filter, the latter an order of magnitude weaker. The polarization grows with molecular length and then saturates, matching trends reported for DNA and peptides. Reversing the drive converts decaying spin into a handedness-locked charge-current pulse (inverse-CISS). We find that once the system is driven, the polarization magnitude scales with an effective spin-orbit coupling: making heavy atoms and curved light-atom backbones indistinguishable at equivalent effective SOC. This enables us to chart how geometry, driving field, and length separate those routes.
