Attosecond correlation dynamics

作者：Ossiander, M.^*; Siegrist, F.; Shirvanyan, V.; Pazourek, R.; Sommer, A.; Latka, T.; Guggenmos, A.; Nagele, S.; Feist, J.; Burgdoerfer, J.; Kienberger, R.; Schultze, M.^*

来源：Nature Physics, 2017, 13(3): 280-+.

DOI：10.1038/NPHYS3941

• HIGH-HARMONIC-GENERATION
• LASER-PULSES
• TIME-DELAY
• HELIUM

Photoemission of an electron is commonly treated as a one-particle phenomenon. With attosecond streaking spectroscopy we observe the breakdown of this single active-electron approximation by recording up to six attoseconds retardation of the dislodged photoelectron due to electronic correlations. We recorded the photon-energy-dependent emission timing of electrons, released from the helium ground state by an extreme-ultraviolet photon, either leaving the ion in its ground state or exciting it into a shake-up state. We identify an optical field-driven d.c. Stark shift of charge-asymmetric ionic states formed after the entangled photoemission as a key contribution to the observed correlation time shift. These findings enable a complete wavepacket reconstruction and are universal for all polarized initial and final states. Sub-attosecond agreement with quantum mechanical ab initio modelling allows us to determine the absolute zero of time in the photoelectric effect to a precision better than 1/25th of the atomic unit of time.

• 出版日期2017-3