Topological aspects of the geometry of DNA and similar chiral molecules have received a lot of attention, but the topology of their electronic structure is less explored. Previous experiments revealed that DNA can efficiently filter spin-polarized electrons between metal contacts, a process called chiral-induced spin selectivity. However, the underlying correlation between chiral structure and electronic spin remains elusive. In this work, we reveal an orbital texture in the band structure, a topological characteristic induced by the chirality. We found that this orbital texture enables the chiral molecule to polarize the quantum orbital. This orbital polarization effect (OPE) induces spin polarization assisted by the spin–orbit interaction of a metal contact and leads to magnetoresistance and chiral separation. The orbital angular momentum of photoelectrons also plays an essential role in related photoemission experiments. Beyond chiral-induced spin selectivity, we predict that the orbital polarization effect could induce spin-selective phenomena even in achiral but inversion-breaking materials.

DNA 和类似手性分子的几何拓扑方面受到了很多关注，但其电子结构的拓扑却很少被探索。先前的实验表明，DNA 可以有效过滤金属接触之间的自旋极化电子，这一过程称为手性诱导自旋选择性。然而，手性结构和电子自旋之间的潜在相关性仍然难以捉摸。在这项工作中，我们揭示了能带结构中的轨道纹理，这是由手性引起的拓扑特征。我们发现这种轨道结构使手性分子能够极化量子轨道。这种轨道极化效应（OPE）在金属接触的自旋轨道相互作用的帮助下诱导自旋极化，并导致磁阻和手性分离。光电子的轨道角动量在相关的光发射实验中也起着至关重要的作用。除了手性诱导的自旋选择性之外，我们预测即使在非手性但破坏反转的材料中，轨道极化效应也可能诱导自旋选择性现象。