Antisite defect qubits in monolayer transition metal dichalcogenides.

Area of Science:

• Quantum Information Sciences
• Materials Science
• Condensed Matter Physics

Background:

• Two-dimensional (2D) materials are atomically thin and externally controllable, presenting opportunities for quantum information science.
• Solid-state spin qubits are crucial for scalable quantum computing, but room-temperature operation remains a challenge.

Purpose of the Study:

• To investigate antisite defects in 2D transition metal dichalcogenides (TMDs) as potential solid-state spin qubits.
• To explore the feasibility of room-temperature qubit operation using these defects.

Main Methods:

• Utilized high-throughput atomistic simulations to identify and analyze antisite defects in TMDs.
• Investigated the electronic and magnetic properties of identified defects, focusing on their ground state characteristics.
• Analyzed optical transitions and intersystem crossing processes for qubit fingerprinting and control.

Main Results:

• Identified several neutral antisite defects in TMDs with paramagnetic triplet ground states located deep within the bulk band gap.
• Confirmed the presence of optical transitions and triplet-singlet intersystem crossing, enabling qubit manipulation.
• Demonstrated initialization and readout principles for an antisite qubit in WS₂, showing stability in multilayer structures.

Conclusions:

• Antisite defects in 2D TMDs provide a controllable solid-state spin qubit system.
• These defect qubits are suitable for room-temperature operation and offer stability against interlayer interactions.
• The study presents a new pathway for scalable, room-temperature spin qubit development in 2D materials.