Full configuration interaction simulations of exchange-coupled donors in silicon using multi-valley effective mass theory. (13th July 2021)

• Record Type: Journal Article
• Authors: Joecker, Benjamin; Baczewski, Andrew D; Gamble, John K; Pla, Jarryd J; Saraiva, André; Morello, Andrea
• Is Part Of: New journal of physics. Volume 23:Number 7(2021)
• Publication Date: 2021-07-13
• Subjects: exchange interaction -- effective mass theory -- spin qubits -- configuration interaction -- donors in silicon; Physics -- Periodicals; Physics; Periodicals; 530.05
• DOI: 10.1088/1367-2630/ac0abf
• Languages: English
• ISSNs: 1367-2630

Abstract

Abstract: Donor spins in silicon have achieved record values of coherence times and single-qubit gate fidelities. The next stage of development involves demonstrating high-fidelity two-qubit logic gates, where the most natural coupling is the exchange interaction. To aid the efficient design of scalable donor-based quantum processors, we model the two-electron wave function using a full configuration interaction method within a multi-valley effective mass theory. We exploit the high computational efficiency of our code to investigate the exchange interaction, valley population, and electron densities for two phosphorus donors in a wide range of lattice positions, orientations, and as a function of applied electric fields. The outcomes are visualized with interactive images where donor positions can be swept while watching the valley and orbital components evolve accordingly. Our results provide a physically intuitive and quantitatively accurate understanding of the placement and tuning criteria necessary to achieve high-fidelity two-qubit gates with donors in silicon. Video Abstract: Video Abstract: Full configuration interaction simulations of exchange-coupled donors in silicon using multi-valley effective mass theory