Soft Quantum Control for Highly Selective Interactions among Joint Quantum Systems

TL;DR

This paper introduces a quantum control method that uses soft temporal modulation to achieve highly selective interactions among near-resonant quantum systems, improving precision in quantum sensing and entanglement.

Contribution

The proposed scheme enables highly selective coupling by adiabatically switching interaction strength, suppressing off-resonant effects, and broadening the applicability of rotating-wave approximation.

Findings

Allows efficient rotating-wave approximation over wide parameters

Eliminates side peaks in quantum sensing experiments

Enables high-fidelity entanglement gates on nuclear spins

Abstract

We propose a quantum control scheme aimed at interacting systems that gives rise to highly selective coupling among their near-to-resonance constituents. Our protocol implements temporal control of the interaction strength, switching it on and off again adiabatically. This soft temporal modulation significantly suppresses off-resonant contributions in the interactions. Among the applications of our method we show that it allows us to perform an efficient rotating-wave approximation in a wide parameter regime, the elimination of side peaks in quantum sensing experiments, and selective high-fidelity entanglement gates on nuclear spins with close frequencies. We apply our theory to nitrogen-vacancy centers in diamond and demonstrate the possibility for the detection of weak electron-nuclear coupling under the presence of strong perturbations.