First Principles Evaluation of Deep-Level Spin Defects in Zinc Oxide

Zinc Oxide (ZnO) has been proposed as a promising host for spin defects for quantum information science and technology (QIST) due to its low spinful nuclei environment [1]. Previous studies have been focused on proposing shallow defects as qubit candidates. However, point defects with deep levels, which are of interest in QIST due to the decoupling with the host bulk states [2], have not been yet identified in this material. Using first principles calculations, we evaluate critical physical properties that point defects must satisfy to be considered as possible spin qubit candidates. For this assessment, we consider defects with triplet ground state, determine their thermodynamic stability within the bandgap, their radiative and non-radiative recombination lifetimes to evaluate the brightness for optical detection, and their coherence times T2 [3]. Through a rigorous screening process, we identified potential candidates from the main group (s- and p- blocks) where the dopant species can occupy the cation vacancy, anion vacancy, or interstitial positions. Additionally, we propose adequate growth synthesis conditions to obtain optimal defect concentrations for experimental evaluation.


[1] Linpeng, X. et al. Phys Rev Appl, 10, 064061 (2018)
[2] Weber, J. R. et al. Proc. Natl Acad. Sci., 107, 8513–8518 (2010)
[3] Ping, Y. and Smart, T. Nat. Comput. Sci., 1, 646–654 (2021)