Mode-resolved, non-local electron–phonon coupling in two-dimensional spectroscopy

Nature Physics, vol. 21, pp. 953–960

Abstract

Abstract Electron–phonon coupling is fundamental to condensed-matter physics, governing various physical phenomena and properties in both conventional and quantum materials. Here we propose and demonstrate two-dimensional electron–phonon coupling spectroscopy that can directly extract the electron–phonon coupling matrix elements for specific phonon modes and different electron energies. Using this technique, we measure the electron energy dependence of the electron–phonon coupling strength for individual phonon modes. It allows us to identify distinct signatures distinguishing non-local Su–Schrieffer–Heeger-type couplings from local Holstein-type couplings. Applying this methodology to a methylammonium lead iodide perovskite, we reveal particularly different properties, for example, temperature dependence or anisotropy, of the electron–phonon couplings of two pronounced phonon modes. Our approach provides insights into the microscopic origin of the electron–phonon coupling and has potential applications in phonon-mediated ultrafast control material properties.

Authors 7

1. Sheng Guan Qu

   Max Planck Institute for Polymer Research

   Affiliation as printed

   Department of Molecular Spectroscopy, Max-Planck Institute for Polymer Research, Mainz, Germany

2. Vishal Kumar Sharma

   Goethe University Frankfurt

   Affiliation as printed

   Institut für Theoretische Physik, Goethe-Universität, Frankfurt am Main, Germany

3. Jaco J. Geuchies Aachen

   Leiden University · Max Planck Institute for Polymer Research

   Affiliation as printed

   Department of Molecular Spectroscopy, Max-Planck Institute for Polymer Research, Mainz, Germany

   Leiden Institute of Chemistry, Leiden University, Leiden, Netherlands

4. Maksim Grechko

   Max Planck Institute for Polymer Research

   Affiliation as printed

   Department of Molecular Spectroscopy, Max-Planck Institute for Polymer Research, Mainz, Germany

5. Mischa Bonn

   Max Planck Institute for Polymer Research

   Affiliation as printed

   Department of Molecular Spectroscopy, Max-Planck Institute for Polymer Research, Mainz, Germany

6. Falko Pientka corresponding

   Goethe University Frankfurt

   Affiliation as printed

   Institut für Theoretische Physik, Goethe-Universität, Frankfurt am Main, Germany

7. Heejae Kim corresponding

   Pohang University of Science and Technology · Max Planck Institute for Polymer Research

   Affiliation as printed

   Department of Molecular Spectroscopy, Max-Planck Institute for Polymer Research, Mainz, Germany

   Department of Physics, Pohang University of Science and Technology, Pohang, Korea