Missing atoms or atom substitutions (point defects) in crystal lattices in two-dimensional (2D) materials are potential hosts for emerging quantum technologies, such as single-photon emitters and spin quantum bits (qubits). First-principles-guided design of quantum defects in 2D materials is paving the way for rational spin qubit discovery. Here we discuss the frontier of first-principles theory development and the challenges in predicting the critical physical properties of point defects in 2D materials for quantum information technology, in particular for optoelectronic and spin-optotronic properties. Strong many-body interactions at reduced dimensionality require advanced electronic structure methods beyond mean-field theory. The great challenges for developing theoretical methods that are appropriate for strongly correlated defect states, as well as general approaches for predicting spin relaxation and the decoherence time of spin defects, are yet to be addressed.
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This material is based on work supported by the Air Force Office of Scientific Research under AFOSR award no. FA9550-YR-1-XYZQ and National Science Foundation under grant no. DMR-1760260. T.J.S. acknowledges support from the LLNL Graduate Research Scholar Program and funding support from LLNL LDRD 20-SI-004.
The authors declare no competing interests.
Peer review information Nature Computational Science thanks the anonymous reviewers for their contribution to the peer review of this work. Handling editor: Jie Pan, in collaboration with the Nature Computational Science team.
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Ping, Y., Smart, T.J. Computational design of quantum defects in two-dimensional materials. Nat Comput Sci 1, 646–654 (2021). https://doi.org/10.1038/s43588-021-00140-w