Possible Hundredfold Enhancement in the Direct Magnetic Coupling of a Single-Atom Electron Spin to a Circuit Resonator
Bahman Sarabi, Peihao Huang, Neil M. Zimmerman · Physical Review Applied · 2019
The use of circuit quantum electrodynamics with single-atom electron spins could lead to scalable, highly coherent qubit schemes for quantum information processing. Reaching the regime of strong magnetic coupling of a photon to a single spin is challenging, though, because of the relatively small spin magnetic moment, and the relatively weak magnetic field of a typical superconducting circuit resonator. The authors show that using a lumped-element resonator with a nanoscale spiral inductor can greatly enhance the photon's magnetic field in the vicinity of the spin trapped in a donor potential. This enables strong magnetic coupling of the resonator to the spin.