High-order above-threshold photoemission from nanotips controlled with two-color laser fields

Beitrag in einer Fachzeitschrift
(Letter)


Details zur Publikation

Autor(en): Seiffert L, Paschen T, Hommelhoff P, Fennel T
Zeitschrift: Journal of the Physics B: Atomic and Molecular Physics
Jahr der Veröffentlichung: 2018
Band: 51
ISSN: 0022-3700
Sprache: Englisch


Abstract

We investigate the process of phase-controlled high-order
above-threshold photoemission from metallic nanotips under bichromatic
laser fields. Experimental photoelectron spectra resulting from
two-color excitation with a moderately intense near-infrared fundamental
field (1560 nm) and its weak second harmonic show a strong sensitivity
on the relative phase and clear indications for a plateau-like structure
that is attributed to elastic backscattering. To explore the relevant
control mechanisms, characteristic features, and particular signatures
from the near-field inhomogeneity, we performed systematic quantum
simulations employing a one-dimensional nanotip model. Besides rich
phase-dependent structures in the simulated above-threshold ionization
photoelectron spectra we find ponderomotive shifts as well as
substantial modifications of the rescattering cutoff as function of the
decay length of the near-field. To explore the quantum or classical
nature of the observed features and to discriminate the two-color
effects stemming from electron propagation and from the ionization rate
we compare the quantum results to classical trajectory simulations. We
show that signatures from direct electrons as well as the modulations in
the plateau region mainly stem from control of the ionization
probability, while the modulation in the cutoff region can only be
explained by the impact of the two-color field on the electron
trajectory. Despite the complexity of the phase-dependent features that
render two-color strong-field photoemission from nanotips intriguing for
sub-cycle strong-field control, our findings support that the
recollision features in the cutoff region provide a robust and reliable
method to calibrate the relative two-color phase.


FAU-Autoren / FAU-Herausgeber

Hommelhoff, Peter Prof. Dr.
Lehrstuhl für Laserphysik
Paschen, Timo
Lehrstuhl für Laserphysik


Autor(en) der externen Einrichtung(en)
Universität Rostock


Zitierweisen

APA:
Seiffert, L., Paschen, T., Hommelhoff, P., & Fennel, T. (2018). High-order above-threshold photoemission from nanotips controlled with two-color laser fields. Journal of the Physics B: Atomic and Molecular Physics, 51. https://dx.doi.org/10.1088/1361-6455/aac34f

MLA:
Seiffert, Lennart, et al. "High-order above-threshold photoemission from nanotips controlled with two-color laser fields." Journal of the Physics B: Atomic and Molecular Physics 51 (2018).

BibTeX: 

Zuletzt aktualisiert 2018-11-08 um 01:40