High-field Magnetotransport Studies of Surface Conducting Diamonds

TL;DR

This study introduces an advanced magnetotransport analysis method for surface conducting diamond devices, revealing high hole mobilities and the dominance of orbital magnetoresistance at high fields, advancing diamond spintronics.

Contribution

It provides a comprehensive, improved theoretical model for analyzing magnetotransport in surface conducting diamond, applicable across various doping strategies and device types.

Findings

Orbital magnetoresistance dominates at high magnetic fields.

Local hole mobilities up to 3000 cm2/Vs observed.

The model accurately explains magnetoconductance across regimes.

Abstract

The observation of strong and tunable spin-orbit interaction (SOI) in surface conducting diamond opens up a new avenue for building diamond-based spintronics. Herein we provide a comprehensive method to analyze the magnetotransport behavior of surface conducting hydrogen-terminated diamond (H-diamond) Hall bar devices and Al/Al2O3/V2O5/H-diamond MOSFETs, respectively. By adopting a significantly improved theoretical magneto transport model, the reduced magnetoconductance can be accurately explained both within and outside the quantum diffusive regime. The model is valid for all doping strategies of surface conducting diamond tested. From this analysis, we find that the orbital magnetoresistance, a classical effect distinct from the SOI, dominates the magnetotransport in surface conducting diamond at high magnetic fields. Furthermore, local hole mobilities as high as 1000 ~ 3000 cm2/Vs have been observed in this work, indicating the possibility of diamond-based electronics with ultra-high hole mobilities at cryogenic temperatures.