Quantum Coherence and Relaxation of Single Spins on Surface Probed by ESR-STM

Abstract

The miniaturization of modern devices to the nanoscale has inspired the development of quantum information processing, in which quantum coherence is of vital importance for both fundamental research and applications. The integration of electron spin resonance with scanning tunneling microscopy (ESR-STM) has emerged as a powerful platform for atomic-scale quantum sensing, simulation and qubit operations on surface. However, the qubit lifetime faces significant challenge due to environmental perturbations in STM circuits, whose underlying mechanisms require a deep and comprehensive understanding. This minireview synthesizes recent advances in studying spin coherence using ESR-STM, focusing on the fundamental decoherence pathways including scattering and tunneling electrons, and magnetic perturbations near the tunnel junction. By elucidating the microscopic origins of decoherence in atomic and molecular spin systems on surface, we provide a framework for developing targeted strategies to enhance quantum coherence of spin qubits on surfaces.