Speaker
Katharina Priebe
(4th Physical Institute – Solids and Nanostructures, University of Göttingen)
Description
Programmable phase-shaping of free-electron wavefunctions is expected
to significantly enhance the capabilities of electron microscopy. In
particular, temporal shaping by optical fields promises time-resolved
electron diffraction and imaging with attosecond precision.
Here, we demonstrate the generation, coherent control and
characterization of free-electron momentum superposition states by
optical phase-modulation using multiple near-fields [1-3]. Our recently
developed “SQUIRRELS” algorithm (Spectral QUantum Interference for the
Regularized Reconstruction of free-ELectron States) reconstructs the
free-electron Wigner function from experimental spectrograms, which are
obtained by recording electron energy spectra for a range of relative
phase delays between two optical near-fields, either at different
frequencies or at spatially separated regions along the electron beam
path.
Free-space propagation over a few millimetre distance leads to the
formation of an attosecond electron pulse train by dispersive reshaping
of the electron density [1]. The temporal shape of the electron quantum
state is contained in the Wigner function, and we successfully applied
SQUIRRELS to experimentally demonstrate the generation of electron
density spikes of only 655 attosecond duration (full-width at
half-maximum) [3].
[1] A. Feist et al., Nature 521, 200-203 (2015)
[2] K. Echternkamp et al., Nature Physics 12, 1000-1004 (2016)
[3] K. Priebe et al., Nature Photonics 11, 793-797 (2017)
Primary authors
Armin Feist
(4th Physical Institute – Solids and Nanostructures, University of Göttingen)
Christopher Rathje
(Institut für Physik, University of Oldenburg)
Claus Ropers
(4th Physical Institute – Solids and Nanostructures, University of Göttingen)
Katharina Priebe
(4th Physical Institute – Solids and Nanostructures, University of Göttingen)
Sascha Schäfer
(Institut für Physik, University of Oldenburg)
Sergey V. Yalunin
(4th Physical Institute – Solids and Nanostructures, University of Göttingen)
Thomas Rittmann
(4th Physical Institute – Solids and Nanostructures, University of Göttingen)
Thorsten Hohage
(Institut für Numerische und Angewandte Mathematik, University of Göttingen)
