The browser you are using is not supported by this website. All versions of Internet Explorer are no longer supported, either by us or Microsoft (read more here: https://www.microsoft.com/en-us/microsoft-365/windows/end-of-ie-support).

Please use a modern browser to fully experience our website, such as the newest versions of Edge, Chrome, Firefox or Safari etc.

Portrait of Tönu Pullerits; Photo: Kennet Ruona

Tönu Pullerits

Professor

Portrait of Tönu Pullerits; Photo: Kennet Ruona

Coherent two-dimensional photocurrent spectroscopy in a PbS quantum dot photocell.

Author

  • Khadga Jung Karki
  • Julia R Widom
  • Joachim Seibt
  • Ian Moody
  • Mark C Lonergan
  • Tönu Pullerits
  • Andrew H Marcus

Summary, in English

Recently there has been growing interest in the role of coherence in electronic dynamics. Coherent multidimensional spectroscopy has been used to reveal coherent phenomena in numerous material systems. Here we utilize a recent implementation of coherent multidimensional spectroscopy-two-dimensional photocurrent spectroscopy-in which we detect the photocurrent from a PbS quantum dot photocell resulting from its interactions with a sequence of four ultrafast laser pulses. We observe sub-picosecond evolution of two-dimensional spectra consistent with multiple exciton generation. Moreover, a comparison with two-dimensional fluorescence spectra of the quantum dots demonstrates the potential of two-dimensional photocurrent spectroscopy to elucidate detailed origins of photocurrent generating electronic state coherence pathways. Since the measurement is based on detecting the photocell current in situ, the method is well suited to study the fundamental ultrafast processes that affect the function of the device. This opens new avenues to investigate and implement coherent optimization strategies directly within devices.

Department/s

  • Chemical Physics
  • NanoLund: Center for Nanoscience

Publishing year

2014

Language

English

Publication/Series

Nature Communications

Volume

5

Document type

Journal article

Publisher

Nature Publishing Group

Topic

  • Atom and Molecular Physics and Optics

Status

Published

ISBN/ISSN/Other

  • ISSN: 2041-1723