Engineered Chirality of One-Dimensional Nanowires

TL;DR

This paper demonstrates the creation of chiral one-dimensional nanowires with engineered spin-orbit interactions, revealing oscillatory quantum transport phenomena and enabling new tests of chirality's role in spin-polarized electron transport.

Contribution

It introduces a method to engineer chiral nanowires with specific spin-orbit interactions, allowing detailed quantum transport studies and simulations of chirality effects.

Findings

Observation of oscillatory transmission resonances in chiral nanowires

Engineered axial spin-orbit interaction within the nanowires

Potential for quantum simulation of chirality-related spin transport phenomena

Abstract

The origin and function of chirality in DNA, proteins, and other building blocks of life represent a central question in biology. Observations of spin polarization and magnetization associated with electron transport through chiral molecules, known collectively as the chiral induced spin selectivity (CISS) effect, suggest that chirality improves electron transfer by inhibiting backscattering. Meanwhile, the role of coherence in the electron transport within chiral nanowires is believed to be important but is challenging to investigate experimentally. Using reconfigurable nanoscale control over conductivity at the LaAlO$_3$/SrTiO$_3$ interface, we create chiral electron potentials that explicitly lack mirror symmetry. Quantum transport measurements on these chiral regions that constitute effective nanowires for the electrons reveal oscillatory transmission resonances as a function of both magnetic field and chemical potential. We interpret these resonances as arising from an engineered axial spin-orbit interaction within the chiral region. The ability to create 1D effective electron waveguides with this specificity and complexity creates new opportunities to test, via analog quantum simulation, theories about the relationship between chirality and spin-polarized electron transport in one-dimensional geometries.