Lightwave valleytronics in a monolayer of tungsten diselenide

F. Langer, C. P. Schmid, S. Schlauderer, M. Gmitra, J. Fabian, P. Nagler, C. Schüller, T. Korn, P. G. Hawkins, J. T. Steiner, U. Huttner, Stephan W Koch, M. Kira, R. Huber

Research output: Contribution to journalArticle

60 Scopus citations

Abstract

As conventional electronics approaches its limits 1, nanoscience has urgently sought methods of fast control of electrons at the fundamental quantum level 2 . Lightwave electronics 3-the foundation of attosecond science 4-uses the oscillating carrier wave of intense light pulses to control the translational motion of the electron's charge faster than a single cycle of light 5-15 . Despite being particularly promising information carriers, the internal quantum attributes of spin 16 and valley pseudospin 17-21 have not been switchable on the subcycle scale. Here we demonstrate lightwave-driven changes of the valley pseudospin and introduce distinct signatures in the optical readout. Photogenerated electron-hole pairs in a monolayer of tungsten diselenide are accelerated and collided by a strong lightwave. The emergence of high-odd-order sidebands and anomalous changes in their polarization direction directly attest to the ultrafast pseudospin dynamics. Quantitative computations combining density functional theory with a non-perturbative quantum many-body approach assign the polarization of the sidebands to a lightwave-induced change of the valley pseudospin and confirm that the process is coherent and adiabatic. Our work opens the door to systematic valleytronic logic at optical clock rates.

Original languageEnglish (US)
Pages (from-to)76-80
Number of pages5
JournalNature
Volume557
Issue number7703
DOIs
StatePublished - May 3 2018
Externally publishedYes

ASJC Scopus subject areas

  • General

Fingerprint Dive into the research topics of 'Lightwave valleytronics in a monolayer of tungsten diselenide'. Together they form a unique fingerprint.

  • Cite this

    Langer, F., Schmid, C. P., Schlauderer, S., Gmitra, M., Fabian, J., Nagler, P., Schüller, C., Korn, T., Hawkins, P. G., Steiner, J. T., Huttner, U., Koch, S. W., Kira, M., & Huber, R. (2018). Lightwave valleytronics in a monolayer of tungsten diselenide. Nature, 557(7703), 76-80. https://doi.org/10.1038/s41586-018-0013-6