Local magnetic resonance of scalar spin chirality

Abstract

Quantum states with finite scalar spin chirality carry an orbital magnetic moment that has so far eluded direct measurement. We show that, whereas uniform electron spin resonance preserves chirality, a local drive breaks the cyclic symmetry and activates chirality-changing transitions, providing direct access to the chiral orbital magnetic moment. Lindblad simulations demonstrate experimentally accessible signatures in platforms with local spin addressability, including electron spin resonance with a scanning tunneling microscope, donor spins in silicon, and quantum-dot spin qubits.