Related papers: Oriented polar molecules trapped in cold helium na…
We demonstrate a novel method to ionize molecules or molecular clusters by proton transfer at temperatures below 1 K. The method yields nascent ions and largely eliminates secondary reactions, even for notoriously "delicate" molecules.…
We have explored the light induced dynamics in superfluid helium nanodroplets with wide-angle scattering in a pump-probe measurement scheme. The droplets are doped with xenon atoms to facilitate the ignition of a nanoplasma through…
We describe a method for depositing nanoscale liquid Au droplets, initially levitated in an ion trap in high vacuum, onto a remote substrate. A levitated Au nanosphere is melted, expelled from the trap, and maintained in the molten state…
Supersonic beams of polar molecules are deflected using inhomogeneous electric fields. The quantum-state selectivity of the deflection is used to spatially separate molecules according to their quantum state. A detailed analysis of the…
The spectroscopy of free radicals and radical containing entrance-channel complexes embedded in superfluid helium nano-droplets is reviewed. The collection of dopants inside individual droplets in the beam represents a micro-canonical…
When fragile molecules such as glycine, polyglicine, alkanes, and alkanethiols are embedded in liquid helium nanodroplets, electron-impact ionization of the beam leads to fragmentation which is as extensive as that of isolated gas-phase…
We present a method which delivers a continuous, high-density beam of slow and internally cold polar molecules. In our source, warm molecules are first cooled by collisions with a cryogenic helium buffer gas. Cold molecules are then…
Doppler cooling is a widely used technique to laser cool atoms and nanoparticles exploiting the Doppler shift involved in translational transformations. The rotational Doppler effect arising from rotational coordinate transformations should…
A method for decelerating a continuous beam of neutral polar molecules is theoretically demonstrated. This method utilizes non-uniform, static electric fields and regions of adiabatic population transfer to generate a mechanical force that…
We study a polar molecule immersed into a superfluid environment, such as a helium nanodroplet or a Bose-Einstein condensate, in the presence of an intense electrostatic field. We show that coupling of the molecular pendular motion, induced…
$^4$He nanodroplets doped with an alkali ion feature a snowball of crystallized layers surrounded by superfluid helium. For large droplets, we predict that a transitional supersolid layer can form, bridging between the solid core and the…
We perform laser spectroscopy at liquid helium temperatures (T=2 K) to investigate single dibenzoterrylene (DBT) molecules doped in anthracene crystals of nanoscopic height fabricated by electrohydrodynamic dripping. Using high-resolution…
We report on the production and study of stable, highly charged droplets of superfluid helium. Using a novel experimental setup we produce neutral beams of liquid helium nanodroplets containing millions of atoms or more that can be ionized…
A new setup for doping helium nanodroplets by means of laser ablation at kilohertz repetition rate is presented. The doping process is characterized and two distinct regimes of laser ablation are identified. The setup is shown to be…
A method of slowing, accelerating, cooling, and bunching molecules and neutral atoms using time-varying electric field gradients is demonstrated with cesium atoms in a fountain. The effects are measured and found to be in agreement with…
Much of our knowledge about dynamics and functionality of molecular systems has been achieved with femtosecond time-resolved spectroscopy. Despite extensive technical developments over the past decades, some classes of systems have eluded…
The field of levitodynamics has made significant progress towards controlling and studying the motion of a levitated nanoparticle. Motional control relies on either autonomous feedback via a cavity or measurement-based feedback via external…
Photoionization spectroscopy and mass spectrometry of doped helium (He) nanodroplets rely on the ability to efficiently detect ions and/or electrons. Using a commercial quadrupole mass spectrometer and a photoelectron-photoion coincidence…
We describe a helium evaporation refrigerator used to cool dynamically polarized proton and deuteron targets for electron-scattering experiments using the CEBAF Large Acceptance Spectrometer CLAS12 at Jefferson Lab. The geometry of the…
Dielectrophoresis (DEP), the motion of polarizable particles in non-uniform electric fields, has become an important tool for the transport, separation, and characterization of microparticles in biomedical and nanoelectronics research. In…