Optical Pump-Probe Scanning Tunneling Microscopy

Abstract

A new microscopy, optical pump-probe scanning tunneling microscopy (OPP-STM), which enables femtosecond temporal resolution and atomic spatial resolution simultaneously, has been realized by combining STM with quantum optical method. Using circularly polarized light for excitation, the measurement of local ultrafast spin dynamics has also become possible. Detection of spin precession has enabled to provide local information of g-factor. Here, the bases for the new microscopy techniques are overviewed.