  Being atomically thin and amenable to external controls, two-dimensional (2D)
materials offer a new paradigm for the realization of patterned qubit
fabrication and operation at room temperature for quantum information sciences
applications. Here we show that the antisite defect in 2D transition metal
dichalcogenides (TMDs) can provide a controllable solid-state spin qubit
system. Using high-throughput atomistic simulations, we identify several
neutral antisite defects in TMDs that lie deep in the bulk band gap and host a
paramagnetic triplet ground state. Our in-depth analysis reveals the presence
of optical transitions and triplet-singlet intersystem crossing processes for
fingerprinting these defect qubits. As an illustrative example, we discuss the
initialization and readout principles of an antisite qubit in WS2, which is
expected to be stable against interlayer interactions in a multilayer structure
for qubit isolation and protection in future qubit-based devices. Our study
opens a new pathway for creating scalable, room-temperature spin qubits in 2D
TMDs.
