Chirality-induced orbital angular momentum selectivity: From helical transport to scattering resolution

We present a computational framework for chirality-induced orbital-angular-momentum (OAM) selectivity in electron transmission and scattering. Using time-dependent Schrödinger equation simulations, electronic wavepackets traversing chiral helical potentials are shown to accumulate well-defined OAM with rotational sense determined by the helix handedness. The efficiency of OAM accumulation strongly depends on the ratio between the wavepacket dimensions and the helix geometric parameters. When anchored to a surface, electrons that approach the helix end are delayed near the surface before full reflection occurs, due to the need to reverse the OAM in order to traverse the helix in the opposite direction. In the presence of spin-orbit coupling, this may support mechanisms of spin accumulation near the edges of molecular helices, suggested for rationalizing experimental evidence of chirality dependent molecular adsorption on magnetic surfaces. Finally, we reveal that wavepackets carrying opposite OAM exhibit spatial resolution when scattered from corrugated surfaces. This suggests that electron deflection observed in Mott polarimetry, often used in photoemission CISS experiments, may be affected not only by the electron spin but also by its orbital angular momentum.