Manipulation of mobile spin coherence using magnetic-field-free electron spin resonance

Electron spin resonance (ESR) has applications in the manipulation of individual electron spins for quantum information processing. In general, ESR requires two external magnetic fields: a static field (B 0) to split the spin states in energy and an oscillating field (B 1) with the frequency resonant to the splitting energy. However, spin manipulation methods relying on real magnetic fields - much broader than the size of individual electrons - are energetically inefficient and unsuitable for future device applications. Here we demonstrate an alternative approach where the spin-orbit interaction of trajectory-controlled electrons induces effective B 0 and B 1 fields. These fields are created when electron spins surf on sound waves along winding semiconductor channels. The resultant spin dynamics - mobile spin resonance - is equivalent to the usual ESR but requires neither static nor time-dependent real magnetic fields to manipulate electron spin coherence.