Atomic Scale Electron Spin Resonance: Towards Electron Spin Qubits on a Surface

The development of scanning tunneling microscope (STM) in early 1980s' has enabled us to characterize single atoms and molecules on surfaces. Building nanostructures in controlled manner and scaling down conventional memory devices using only handful of magnetic atoms in the STM have been one of the major focuses in this field. Here, I first introduce a recent advance of STM by combining the conventional electron spin resonance (ESR), which picked up the advantages of the two techniques, high spatial resolution of STM and high energy resolution of ESR, enabling to drive and detect spin resonance of individual atoms on surfaces. Then, I continue an introduction to a successful implementation of pulsed-ESR into STM to coherently control individual atomic and molecular spins on surfaces, paving a way towards on-surface electron spin qubits at the atomic scale.