Spin-polarized Majorana zero modes in proximitized superconducting penta-silicene nanoribbons

Abstract

We theoretically propose penta-silicene nanoribbons (p-SiNRs) with induced p-wave superconductivity as a platform for the emergence of spin-polarized Majorana zero-modes (MZMs). The model explicitly considers the key ingredients of well-known Majorana hybrid nanowire setups: Rashba spin-orbit coupling, magnetic field perpendicular to the nanoribbon plane, and first nearest neighbor hopping with p-wave superconducting pairing. The energy spectrum of the system, as a function of chemical potential, reveals the existence of MZMs with a well-defined spin orientation localized at the opposite ends of both the top and bottom chains of the p-SiNR, associated with well-localized and nonoverlapping wave function profiles. Well-established experimental techniques enable the fabrication of highly ordered p-SiNRs, complemented by a thin lead film on top, responsible for inducing p-wave superconductivity through proximity effect. Moreover, the emergence of MZMs with explicit opposite spin orientations for some set of model parameters opens a new avenue for exploring quantum computing operations, which accounts for both MZMs and spin properties, as well as for new MZMs probe devices based on spin-polarized electronic transport mechanisms.

Sequencing one-dimensional Majorana materials for topological quantum computing

“…The band structure of the penta-silicene reveals several topological phase transitions. For the corresponding finite case, the energy spectrum as a function of chemical potential displays different configurations of MZMs, as indicated in figure 5 of our previous article [44]. These p-SiNRs should host MZMs at their ends, which could be detected in situ by tunneling spectroscopy.…”

“…In the same vein, we previously designed another scalable platform based on the straight, highly perfect, narrow (0.8 nm in width), single-stranded penta-silicene NRs (p-SiNRs) spontaneously self-aligned at room temperature along the [1 10] direction of a silver (110) template [44]. Similar conditions, as described above for the zHNRs, cause the structure of the p-SiNRs to turn into a double spin-polarized Kitaev chain, with each of the edge displaying spin up or down orientations.…”