Proposal for all-electrical spin manipulation and detection for a single molecule on boron-substituted graphene

TL;DR

This paper demonstrates a method for all-electrical manipulation and detection of spin states in a molecular spinterface, specifically using FeTPP on boron-substituted graphene, enabling reversible spin switching and spin-polarized transport.

Contribution

It introduces a first-principles approach to control and detect spin states in molecular interfaces with a feasible 3-terminal setup for spintronics applications.

Findings

Reversible spin switching between S=1 and S=3/2 states achieved.

Significant spin polarization in transport near the Fermi energy.

Strong hybridization between Fe-$d_{z^2}$ and B-$p_z$ orbitals underpins spin control.

Abstract

All-electrical writing and reading of spin states attract considerable attention for their promising applications in energy-efficient spintronics devices. Here we show, based on rigorous first-principles calculations, that the spin properties can be manipulated and detected in molecular spinterfaces, where an iron tetraphenyl porphyrin (FeTPP) molecule is deposited on boron-substituted graphene (B-G). Notably, a reversible spin switching between the $S=1$ and $S=3/2$ states is achieved by a gate electrode. We can trace the origin to a strong hybridization between the Fe-$d_{{z}^2}$ and B-$p_z$ orbitals. Combining density functional theory with nonequilibrium Green's function formalism, we propose an experimentally feasible 3-terminal setup to probe the spin state. Furthermore, we show how the in-plane quantum transport for the B-G, which is non-spin polarized, can be modified by FeTPP, yielding a significant transport spin polarization near the Fermi energy ($>10\%$ for typical coverage). Our work paves the way to realize all-electrical spintronics devices using molecular spinterfaces.