Atomistic tight-binding Hartree-Fock calculations of multielectron configurations in P-doped silicon devices:...

Area of Science:

• Quantum Computing
• Condensed Matter Physics
• Computational Materials Science

Background:

• Donor-based quantum devices in silicon offer potential for quantum computing and simulations.
• Precise dopant placement is key to controlling quantum properties in these devices.

Purpose of the Study:

• To perform atomistic calculations of many-electron states in single phosphorus atoms and dimers in silicon.
• To analyze electron energies, charging, and binding energies as a function of impurity separation.

Main Methods:

• Utilized self-consistent tight-binding Hamiltonians and Hartree-Fock equations for atomistic calculations.
• Computed Coulomb and exchange integrals without reliance on atomic orbital sets.
• Validated the tight-binding Hartree-Fock protocol against configuration-interaction calculations.

Main Results:

• The formalism accurately estimates electron-electron repulsion energy for single phosphorus atoms.
• Calculations predict an antiferromagnetic ground state for a two-electron system in phosphorus dimers.
• A weakly bound three-electron state was observed in phosphorus dimers within considered separations.

Conclusions:

• The atomistic, self-consistent method provides accurate insights into electron states in silicon-based quantum devices.
• Results offer a pathway to understanding and optimizing donor-based quantum systems for computing and simulation.