67 citations · 195 across the 15 of their papers we have counts for
17 papers
Automation in quantum logic experiments with cold molecular ions
Richard Karl, Meissa Diouf, Aleksandr Shlykov +2
Modern experiments with cold molecular ions have reached a high degree of complexity requiring frequent sample preparation, state initialization and protocol execution while demand…
Control of chemical reactions in radiofrequency ion traps
Prerna Paliwal, Jutta Toscano, Stefan Willitsch
Over the past years, radiofrequency ion traps have become an attractive platform for studying chemical reactions as they enable a high degree of control over ion-molecule dynamics.…
Isomer- and state-dependent ion-molecule reactions between Coulomb-crystallised Ca ions and 1,2-dichloroethene
Lei Xu, Richard Karl, Jutta Toscano +1
We report a systematic investigation of isomer- and state-dependent reactions between Coulomb-crystallised laser-cooled Ca ions and \emph{cis/trans}-1,2-dichloroethene (DCE) is…
The role of spectator modes in the quantum-logic spectroscopy of single trapped molecular ions
Mikolaj Roguski, Aleksandr Shlykov, Ziv Meir +1
Quantum-logic spectroscopy has become an increasingly important tool for the state detection and readout of trapped atomic and molecular ions which do not possess easily accessible…
Ion counting and temperature determination of Coulomb-crystallized laser-cooled ions in traps using convolutional neural networks
Yanning Yin, Stefan Willitsch
Coulomb crystals -- ordered structures of cold ions confined in ion traps -- find applications in a variety of research fields. The number and temperature of the ions forming the C…
Coupling trapped ions to a nanomechanical oscillator
Moritz Weegen, Martino Poggio, Stefan Willitsch
Cold ions in traps are well-established, highly controllable quantum systems with a wide variety of applications in quantum information, precision spectroscopy, clocks and chemistr…
Cold trapped molecular ions and hybrid platforms for ions and neutral particles
Markus Deiß, Stefan Willitsch, Johannes Hecker Denschlag
We review recent progress in the field of cold trapped molecular ions. A new generation of collision and cold chemistry experiments between atoms and ions has emerged, where cold a…
Experimental implementation of laser cooling of trapped ions in strongly inhomogeneous magnetic fields
Christian Mangeng, Yanning Yin, Richard Karl +1
We demonstrate the Doppler laser cooling of Ca ions confined in a segmented linear Paul trap in the presence of a strong quadrupolar magnetic field generated by two perm…
Optimized strategies for the quantum-state preparation of single trapped nitrogen molecular ions
Aleksandr Shlykov, Mikolaj Roguski, Stefan Willitsch
This work examines optimized strategies for the preparation of single molecular ions in well-defined rotational quantum states in an ion trap with the example of the molecular nitr…
Trapping and sympathetic cooling of conformationally selected molecular ions
Lei Xu, Jutta Toscano, Stefan Willitsch
We report the generation, trapping and sympathetic cooling of individual conformers of molecular ions with the example of cis- and trans-meta-aminostyrene. Following conformational…
Conformational and state-specific effects in reactions of 2,3-dibromobutadiene with Coulomb-crystallized calcium ions
Ardita Kilaj, Silvan Käser, Jia Wang +7
Recent advances in experimental methodology enabled studies of the quantum-state and conformational dependence of chemical reactions under precisely controlled conditions in the ga…
Charge transfer of polyatomic molecules in ion-atom hybrid traps: Stereodynamics in the millikelvin regime
Alexandre Voute, Alexander Dörfler, Laurent Wiesenfeld +4
Rate constants for the charge transfer reaction between NH and Rb in the mK regime are measured in an ion-atom hybrid trap and are found to be lower than the Langev…
Development and characterization of high-frequency sources for supersonic beams of fluorine radicals
Patrik Straňák, Ludger Ploenes, Simon Hofsäss +3
We present and compare two high-pressure, high-frequency electric-discharge sources for the generation of supersonic beams of fluorine radicals. The sources are based on dielectric…
Rotational state-changing collisions between N and Rb at low energies
A. D. Dörfler, E. Yurtsever, P. Villarreal +3
We present a theoretical study of rotationally elastic and inelastic collisions between molecular nitrogen ions and Rb atoms in the sub-Kelvin temperature regime prevalent in ion-a…
Superstatistical energy distributions of an ion in an ultracold buffer gas
I. Rouse, S. Willitsch
An ion in a radiofrequency ion trap interacting with a buffer gas of ultracold neutral atoms is a driven dynamical system which has been found to develop a non-thermal energy distr…
Optimised surface-electrode ion-trap junctions for experiments with cold molecular ions
Arezoo Mokhberi, Roman Schmied, Stefan Willitsch
We discuss the design and optimisation of two types of junctions between surface-electrode radiofrequency ion-trap arrays that enable the integration of experiments with sympatheti…
Temperature-independent quantum logic for molecular spectroscopy
J. Mur-Petit, J. Pérez-Ríos, J. Campos-Martínez +3
We propose a fast and non-destructive spectroscopic method for single molecular ions that implements quantum logic schemes between an atomic ion and the molecular ion of interest.…