Temperature dependence of divacancy spin coherence in implanted silicon carbide

Abstract

Spin defects in silicon carbide (SiC) have attracted increasing interest due to their excellent optical and spin properties, which are useful in quantum information processing. In this paper, we systematically investigate the temperature dependence of the spin properties of divacancy defects in implanted 4\emph{H}-SiC. The zero-field splitting parameter $D$, the inhomogeneous dephasing time $T_2^{*}$, the coherence time $T_2$, and the depolarization time $T_1$ are extensively explored in a temperature range from 5 to 300 K. Two samples implanted with different nitrogen molecule ion fluences ($\rm {N_2}^{+}$, $1\times 10^{14}/\rm cm^{2}$ and $1\times 10^{13}/\rm cm^{2}$) are investigated, whose spin properties are shown to have similar temperature-dependent behaviors. Still, the sample implanted with a lower ion fluence has longer $T_{2}$ and $T_{1}$. We provide possible theoretical explanations for the observed temperature-dependent dynamics. Our work promotes the understanding of the temperature dependence of spin properties in solid-state systems, which can be helpful for constructing wide temperature-range thermometers based on the mature semiconductor material.