Coherent driving of quantum spins via electrically controlled nonlinear magnetization precessions in quantum-classical spin hybrids

Coherent drives that are spatially local and at the same time add minimal decoherence when manipulating quantum spins, are of significant interest for quantum technology applications. Spin-spin interactions in quantum impurity spin [like Nitrogen vacancy (NV) center]-nanomagnet hybrids provide a platform where spintronic tools controlling nanomagnet dynamics, can be leveraged to coherently drive the quantum spin. However, decoupling coherent and incoherent dynamics is required for attaining large quality factors. Here, we propose to utilize a novel dynamics regime where electrically controlled nonlinear magnetization precessions of a nanomagnet [Nature materials 11, 39 (2012)] can be used to drive the quantum spin to arbitrary quantum states over the Bloch sphere. We demonstrate that the coherent and incoherent dynamics are decoupled in this regime, thereby showing that such quantum-classical spin hybrids can serve as a coherent drive that is local, electrically-controlled, and decoupled from incoherent dynamics.