Lecture: Spatially-resolved spectroscopic investigation of single-molecule energy dynamics with scanning tunneling microscopy

13.11.2017, 10:30

Dr. Hiroshi Imada Surface and Interface Science Laboratory, RIKEN, Japan

Place:
Seminar Room A1.500, MPL, Staudtstr. 2, 91058 Erlangen


Abstract:

The electronic excitation of molecules triggers diverse phenomena, such as luminescence, photovoltaic effects, and various chemical dynamics. Those dynamic processes at the excited states are the bases of various important energy conversion devices. Although properties of the excited states are widely investigated by optical spectroscopy, detailed characterization of the excited states at the molecular scale spatial resolution remains infeasible because of the diffraction limit in the optical methods.

In this presentation, I describe the development of a novel single-molecule absorption/emission spectroscopy with an unprecedented sensitivity and spatial resolution [1] and its application to the real-space investigation of intermolecular energy transfer [2]. Our technique is based on detection of photons induced by the tunneling current of low-temperature scanning tunneling microscopy (STM), which provides spectroscopic information of the molecular excited states together with the atomically precise distribution of the frontier molecular orbitals which governs the molecular excited state.

References

1.       H. Imada, K. Miwa, M. Imai-Imada, S. Kawahara, K. Kimura and Y. Kim, Phys. Rev. Lett. 119, 013901 (2017).

2.       H. Imada, K. Miwa, M. Imai-Imada, S. Kawahara, K. Kimura and Y. Kim, Nature. 538, 364 (2016).