Electron Spin Decoherence in Silicon Carbide Nuclear Spin Bath

TL;DR

This study demonstrates that defect centers in silicon carbide exhibit longer electron spin coherence times than NV centers in diamond, due to suppressed heteronuclear flip-flop processes, making SiC promising for quantum computing.

Contribution

It reveals the unexpectedly longer coherence times of SiC defect centers compared to diamond NV centers, highlighting their potential for quantum information applications.

Findings

SiC defect centers have longer coherence times than diamond NV centers in strong magnetic fields.

Suppression of heteronuclear-spin flip-flop processes enhances electron spin coherence.

Counter-intuitive coherence time advantage despite higher $^{29}$Si abundance.

Abstract

In this paper, we study the electron spin decoherence of single defects in silicon carbide (SiC) nuclear spin bath. We find that, although the natural abundance of $^{29}\rm{Si}$ ($p_{\rm{Si}}=4.7\%$) is about 4 times larger than that of $^{13}{\rm C}$ ($p_{\rm{C}}=1.1\%$), the electron spin coherence time of defect centers in SiC nuclear spin bath in strong magnetic field ($B>300~\rm{Gauss}$) is longer than that of nitrogen-vacancy (NV) centers in $^{13}{\rm C}$ nuclear spin bath in diamond. The reason for this counter-intuitive result is the suppression of heteronuclear-spin flip-flop process in finite magnetic field. Our results show that electron spin of defect centers in SiC are excellent candidates for solid state spin qubit in quantum information processing.