Exceptional homochirality and spin absorption via meniscus-driven chiral symmetry breaking

Introducing chirality into material systems typically relies on incorporating stereocenters during synthesis or the use of chiral additives. Alternatively, physical chiral induction offers unique advantages to chemical approaches in their ability to modulate homochirality and helical sense without changing the chemical structure. Here, a remarkably straightforward approach to inducing molecular-scale chiral symmetry breaking by manipulating the macroscopic symmetry of the meniscus during evaporative assembly is reported. This meniscus-driven approach led to orders of magnitude boost of circular dichroism (CD) dissymmetric absorption while yielding complete homochirality over centimeter scale across multiple class of intrinsically achiral semiconducting polymers. Fluid dynamic simulations show that sufficiently tilting the meniscus leads to a vorticity gradient that twists the polymer nanofibers into consistent helical sense across the meniscus, a mechanism fully supported by multi-scale morphological characterizations. Such exceptional homochirality yields a three-fold increase in spin-mixing conductance across the polymer/ferromagnet interface compared to the heterochiral counterpart. Attributed to chirality-enhanced spin-orbit coupling comparable to that of conventional heavy metals, our findings pave the way for solution-processable chiral spintronics operable at ambient conditions.