Chirality-Induced Majorana Zero Modes and Majorana Polarization

ACS Nano. 2024 Dec 17;18(50):34126-34133. doi: 10.1021/acsnano.4c10395. Epub 2024 Dec 5.

Abstract

Realizing Majorana Fermions has always been regarded as a crucial and formidable task in topological superconductors. In this work, we report a physical mechanism and a material platform for realizing Majorana zero modes (MZMs). This material platform consists of open circular helix molecule (CHM) proximity coupled with an s-wave superconductor (under an external magnetic field) or interconnected-CHM chain coupled with a phase-bias s-wave superconducting heterostructure (without any external magnetic field). MZMs generated here are tightly associated with the structural chirality in CHMs. Notably, the left- and right-handedness results in completely opposite Majorana polarization (MP), leading us to refer to this phenomenon as chirality-induced MP (CIMP). Importantly, the local CIMP is closely linked to chirality-induced spin polarization, providing us with an effective way to regulate MZMs through the chirality-induced spin selectivity (CISS) effect. Furthermore, MZMs can be detected by the spin-polarized current measurements related to the CISS in chiral materials.

Keywords: Majorana zero modes; chirality-induced Majorana polarization; chirality-induced spin selectivity; circular helix molecules; topological superconductor.