78th CEMS Colloquium

Speaker

Dr. Tetsuo Hanaguri (Team Leader, Emergent Phenomena Measurement Research Team, RIKEN CEMS)

Date

17:00 - 18:00, December 25, 2019 (Wednesday)

Venue

Okochi-Hall, RIKEN

Title

Spectroscopic-imaging scanning tunneling microscopy on emergent phenomena

Abstract

Scanning-tunneling-microscopy (STM) is not only an atomic-resolution imaging tool, but also able to measure the electron excitation spectrum by tunneling spectroscopy. Spectroscopic-imaging STM (SI-STM) is an ultimate combination of these two functions; the tunneling spectrum is acquired at every pixel of the atomic-resolution STM topography and thus atomically registered energy-resolved spectroscopic images can be obtained. Fourier analyses of the volume spectroscopic data allow us to access momentum space as well. Since SI-STM works under extreme conditions such as low temperature and high magnetic field, it can be a powerful tool to investigate electronic states behind various emergent phenomena such as high-temperature superconductivity and topological quantum phenomena. I will briefly review how this beautiful technique has been developed and will show how the cutting-edge SI-STM technology elucidates electronic states of emergent materials, using the iron-based superconductor as an example.