229 citations · 926 across the 15 of their papers we have counts for
15 papers
Controlling isomer population using a dual-oscillator infrared free-electron laser
América Y. Torres-Boy, Anoushka Ghosh, Myles B. T. Osenton +8
We report on the control and characterization of the isomer population of ions inside superfluid helium nanodroplets, using two-color operation of a dual-oscillator infrared free-e…
Comprehensive peak-width analysis in matter-wave diffraction under grazing incidence conditions
Lee Yeong Kim, Do Won Kang, Jong Chan Lee +3
Thermal energy atom scattering at a surface with grazing incidence conditions is an innovative method for investigating dispersive atom-surface interactions with potential applicat…
Infrared super-resolution wide-field microscopy using sum-frequency generation
Richarda Niemann, Sören Wasserroth, Guanyu Lu +6
Super-resolution microscopy in the visible is an established powerful tool in several disciplines. In the infrared (IR) spectral range, however, no comparable schemes have been dem…
Second-harmonic phonon spectroscopy of -quartz
Christopher J. Winta, Sandy Gewinner, Wieland Schöllkopf +2
We demonstrate midinfrared second-harmonic generation as a highly sensitive phonon spectroscopy technique that we exemplify using -quartz (SiO) as a model system. A midinfra…
Second Harmonic Generation from Critically Coupled Surface Phonon Polaritons
Nikolai Christian Passler, Ilya Razdolski, Sandy Gewinner +3
Mid-infrared nanophotonics can be realized using sub-diffractional light localization and field enhancement with surface phonon polaritons in polar dielectric materials. We experim…
Effects of Crystal Anisotropy on Optical Phonon Resonances in the Mid-Infrared Second Harmonic Response of SiC
Alexander Paarmann, Ilya Razdolski, Sandy Gewinner +2
We study the effects of crystal anisotropy on optical phonon resonances in the second harmonic generation (SHG) from silicon carbide (SiC) in its Reststrahl region. By comparing ex…
Resonant enhancement of second harmonic generation in the mid-infrared using localized surface phonon polaritons in sub-diffractional nanostructures
Ilya Razdolski, Yiguo Chen, Alexander J. Giles +8
We report on strong enhancement of mid-infrared second harmonic generation (SHG) from SiC nanopillars due to the resonant excitation of localized surface phonon-polaritons within t…
Imaging the He quantum halo state using a free electron laser
S. Zeller, M. Kunitski, J. Voigtsberger +24
We report on coulomb explosion imaging of the wavefunction of the quantum halo system He. Each atom of this system is ionized by tunnelionization in a femto second laser pulse…
Observation of the Efimov state of the helium trimer
Maksim Kunitski, Stefan Zeller, Jörg Voigtsberger +9
Quantum theory dictates that upon weakening the two-body interaction in a three-body system, an infinite number of three-body bound states of a huge spatial extent emerge just befo…
Single photon double ionization of the helium dimer
T. Havermeier, T. Jahnke, K. Kreidi +16
We show that a single photon can ionize the two helium atoms of the helium dimer in a distance up to 10 °A. The energy sharing among the electrons, the angular distributions of the…
Interatomic Coulombic Decay following Photoionization of the Helium Dimer: Observation of Vibrational Structure
T. Havermeier, T. Jahnke, K. Kreidi +15
Using synchrotron radiation we simultaneously ionize and excite one helium atom of a helium dimer (He_2) in a shakeup process. The populated states of the dimer ion (i.e. He^[*+](n…
Coherent reflection of He atom beams from rough surfaces at near-grazing incidence
Bum Suk Zhao, H. Christian Schewe, Gerard Meijer +1
We here report coherent reflection of thermal He atom beams from various microscopically rough surfaces at grazing incidence. For a sufficiently small normal component of the…
Emerging beam resonances in atom diffraction from a reflection grating
Bum Suk Zhao, Gerard Meijer, Wieland Schöllkopf
We report on the observation of emerging beam resonances, well known as Rayleigh-Wood anomalies and threshold resonances in photon and electron diffraction, respectively, in an ato…
Trapping of Rb atoms by ac electric fields
Sophie Schlunk, Adela Marian, Peter Geng +3
We demonstrate trapping of an ultracold gas of neutral atoms in a macroscopic ac electric trap. Three-dimensional confinement is obtained by switching between two saddle-point conf…
Determination of Atom-Surface van der Waals Potentials from Transmission-Grating Diffraction Intensities
R. E. Grisenti, W. Schoellkopf, J. P. Toennies +2
Molecular beams of rare gas atoms and D_2 have been diffracted from 100 nm period SiN_x transmission gratings. The relative intensities of the diffraction peaks out to the 8th orde…