Robust Spin Interconnect with Isotropic Spin Dynamics in Chemical Vapour Deposited Graphene Layers and Boundaries

TL;DR

This study demonstrates that large-area CVD graphene exhibits uniform, isotropic spin transport properties at room temperature, even with multilayer patches and boundaries, supporting its use in scalable spintronic circuits.

Contribution

It reveals universal, isotropic spin dynamics in inhomogeneous CVD graphene layers and boundaries, advancing understanding for robust spin interconnects in spintronics.

Findings

Spin lifetime is uniform and isotropic across different graphene layers.

Spin relaxation mechanisms involve Elliott-Yafet and Dyakonov-Perel processes.

Multilayer patches do not impair spin transport at room temperature.

Abstract

The utilization of large-area graphene grown by chemical vapour deposition (CVD) is crucial for the development of scalable spin interconnects in all-spin-based memory and logic circuits. However, the fundamental influence of the presence of multilayer graphene patches and their boundaries on spin dynamics has not been addressed yet, which is necessary for basic understanding and application of robust spin interconnects. Here, we report universal spin transport and dynamic properties in specially devised single layer, bi-layer, and tri-layer graphene channels and their layer boundaries and folds that are usually present in CVD graphene samples. We observe uniform spin lifetime with isotropic spin relaxation for spins with different orientations in graphene layers and their boundaries at room temperature. In all the inhomogeneous graphene channels, the spin lifetime anisotropy ratios for spins polarized out-of-plane and in-plane are measured to be close to unity. Our analysis shows the importance of both Elliott-Yafet and Dyakonov-Perel mechanisms, with an increasing role of the latter mechanism in multilayer channels. These results of universal and isotropic spin transport on large-area inhomogeneous CVD graphene with multilayer patches and their boundaries and folds at room temperature prove its outstanding spin interconnect functionality, beneficial for the development of scalable spintronic circuits.