M. Weegen, M. Poggio and S. Willitsch,
"Coupling trapped ions to a nanomechanical oscillator"
Phys. Rev. Lett. (in press) (arXiv:2312.00576) (supporting data at https://zenodo.org/records/10232995)
A. Mishra, J. Kim, S. K. Kim and S. Willitsch,
"Isomeric and rotational effects in the chemi-ionisation of 1,2-dibromoethene with metastable neon atoms"
L. Ploenes, P. Straňák, A. Mishra, X. Liu, J. Pérez-Ríos and S. Willitsch,
"Collisional alignment and molecular rotation control chemi-ionization of individual conformers"
J. Toscano,
"Rotational-state-selected Carbon Astrochemistry"
L. Xu, J. Toscano, and S. Willitsch,
"Trapping and sympathetic cooling of conformationally selected molecular ions"
Phys. Rev. Lett. 132, 083001(2024) (arXiv:2308.03935) (supporting data at https://zenodo.org/records/10938912)
M. Deiß, S. Willitsch and J. H. Denschlag,
"Cold trapped molecular ions and hybrid platforms for ions and neutral particles"
R. Karl, Y. Yin and S. Willitsch,
"Laser Cooling of Trapped Ions in Strongly Inhomogeneous Magnetic Fields"
Mol. Phys. 122 (2023), 2199099, (arXiv:2212.11863) (supporting data at https://zenodo.org/records/7445811)
C. Mangeng, Y Yin, R. Karl, and S. Willitsch,
"Experimental implementation of laser cooling of trapped ions in strongly inhomogeneous magnetic fields"
A. Shlykov, M. Roguski, and S. Willitsch,
"Optimized strategies for the quantum-state preparation of single trapped nitrogen molecular ions"
Adv. Quantum Technol. (2023), 2300268 (arXiv:2309.03035) (supporting data at https://zenodo.org/records/8273494)
A. Voute, A. Dörfler, L. Wiesenfeld, O. Dulieu, F. Gatti, D. Peláez and S. Willitsch,
"Charge transfer of polyatomic molecules in ion-atom hybrid traps: Stereodynamics in the millikelvin regime"
A. Kilaj, S. Käser, J. Wang, P. Straňák, M. Schwilk, L. Xu, O. A. v. Lilienfeld, J. Küpper, M. Meuwly, and S. Willitsch,
"Conformational and state-specific effects in reactions of 2,3-dibromobutadiene with Coulomb-crystallized calcium ions"
Phys. Chem. Chem. Phys. 25 (2023), 13933–13945 (arXiv:2303.11813) (supporting data at https://zenodo.org/record/7892235)
M. Sinhal and S. Willitsch,
"Molecular-ion quantum technologies"
p. 305 ff. in "Photonic Quantum Technologies: Science and Applications", ed. M. Benyoucef, Wiley-VCH 2023 (arXiv:2204.08814)
X. Xing, H. D. Silva Jr, R. Vexiau, N. B. Maafa, S. Willitsch and O. Dulieu,
"Ion loss events in a cold Rb-Ca+ hybrid trap: photodissociation, black-body radiation and non-radiative charge exchange"
M. Sinhal, A. Johnson and S. Willitsch,
"Frequency stabilisation and SI tracing of mid-infrared quantum-cascade lasers for precision molecular spectroscopy"
Mol. Phys. e2144519 (2022) (arXiv:2209.06471) (supporting data at https://zenodo.org/record/7035071)
M. Bertrand , A. Shlykov, M. Shahmohamadi, M. Beck , S. Willitsch and J. Faist
”A High-Power, Narrow-Linewidth Distributed-Feedback Quantum-Cascade Laser for Molecular Spectroscopy”
S. Willitsch,
"Fundamental Research in Chemistry and the SCS: Past, Present, Future"
P. Stranák, L. Ploenes, S. Hofsäss, K. Dulitz, F. Stienkemeier and S. Willitsch,
"Development and characterization of high-repetition-rate sources for supersonic beams of fluorine radicals"
Rev. Sci. Instr. 92 (2021), 103203 (arXiv:2108.05952) (supporting data at 10.5281/zenodo.5176059)
T. Damjanovic, S. Willitsch, N. Vanhaecke, H. Haak, G. Meijer, J. Cromieres, D. Zhang,
"A New Design for a Traveling-Wave Zeeman Decelerator: I. Theory"
T. Damjanovic, S. Willitsch, N. Vanhaecke, H. Haak, G. Meijer, J. Cromieres, D. Zhang,
"A New Design for a Traveling-Wave Zeeman Decelerator: II. Experiment"
A. Kilaj, J. Wang, P. Straňák, M. Schwilk, U. Rivero, L. Xu, O. A v. Lilienfeld, J. Küpper, and S. Willitsch,
"Conformer-specific polar cycloaddition of dibromobutadiene with trapped propene ions"
Nat. Commun. 12 (2021), 6047 (arXiv:2107.13858) (supporting data at 10.5281/zenodo.5525788)
L. Ploenes, P. Straňák, H. Gao, J. Küpper and S. Willitsch,
”A novel crossed-molecular-beam experiment for investigating reactions of state- and conformationally selected strong-field-seeking molecules”
Mol. Phys. 119 (2021), e1965234 (arxiv: 2105.06427) (supporting data at 10.5281/zenodo.5176041)
M. Sinhal, Z. Meir, and S. Willitsch,
”Non-destructive State Detection and Spectroscopy of Single Molecules”
D. Husmann, L. G. Bernier, M. Bertrand, D. Calonico, K. Chaloulos, G. Clausen, C. Clivati, J. Faist, E. Heiri, U. Hollenstein, A. Johnson, F. Mauchle, Z. Meir, F. Merkt, A. Mura, G. Scalari, S. Scheidegger, H. Schmutz, M. Sinhal, S. Willitsch, and J. Morel,
”SI-traceable frequency dissemination at 1572.06 nm in a stabilized fiber network with ring topology”
Opt. Expr. 29 (2021), 24592 (arXiv:2104.09966v1) (supporting data at 10.5281/zenodo.5040076)
U. Rivero, H. T. Turan, M. Meuwly and S. Willitsch,
”Reactive atomistic simulations of Diels-Alder-type reactions: Conformational and dynamic effects in the polar cycloaddition of 2,3-dibromobutadiene radical ions with maleic anhydride”
Mol. Phys. 119 (2021), e1825852 (arXiv 2010.00464) (supporting data at https://zenodo.org/records/3701284)
T. Damjanovic, N. Vanhaecke, J. Cromieres, H. Haak, G. Meijer, S. Willitsch and D. Zhang,
”A traveling wave Zeeman decelerator”
A. D. Dörfler, E. Yurtsever, P. Villarreal, T. González-Lezana, F. A. Gianturco and S. Willitsch,
”Rotational state-changing collisions between N2+ and Rb at low energies”
Z. Meir, M. Sinhal, M. S. Safronova and S. Willitsch,
"Combining experiments and relativistic theory for establishing accurate radiative quantities in atoms: the lifetime of the 2P3/2 state in 40Ca+"
Phys. Rev. A 101 (2020), 012509 (arXiv 1909.1051) (supporting data at 10.5281/zenodo.3532722)
M. Sinhal, Z. Meir, K. Najafian, G. Hegi and S. Willitsch,
"Quantum non-demolition state detection and spectroscopy of single trapped molecules"
Science 367 (2020), 1213 (arXiv 1910.11600) (supporting data at 10.5281/zenodo.3532942)
K. Najafian, Z. Meir, M. Sinhal and S. Willitsch,
"Identification of molecular quantum states using phase-sensitive forces"
Nat. Commun. 11 (2020), 4470 (arXiv 2004.05306) (supporting data at 10.5281/zenodo.3898046)
A. Kilaj, H. Gao, D. Tahchieva, R. Ramakrishnan, D. Bachmann, D. Gillingham, O. A. von Lilienfeld, J. Küpper and S. Willitsch,
"Quantum-chemistry-aided identification, synthesis and experimental validation of model systems for conformationally controlled reaction studies: Separation of the conformers of 2,3-dibromobuta-1,3-diene in the gas phase"
J. Wang, A. Kilaj, L. He, K. Dlugolecki, S. Willitsch and J. Küpper,
”Spatial separation of the conformers of methyl vinyl ketone”
K. Najafian, Z. Meir and S. Willitsch,
”From megahertz to terahertz qubits encoded in molecular ions: theoretical analysis of dipole-forbidden spectroscopic transitions in N2+”
Phys. Chem. Chem. Phys. 22 (2020), 23083 (arxiv 2007.11097) (supporting data at 10.5281/zenodo.4006578)
P. Fountas, M. Poggio and S. Willitsch,
"Classical and quantum dynamics of a trapped ion coupled to a charged nanowire”
Z. Meir, G. Hegi, K. Najafian, M. Sinhal and S. Willitsch,
"State-selective coherent motional excitation as a new approach for the manipulation, spectroscopy and state-to-state chemistry of single molecular ions”
F. A. Gianturco, A. D. Dörfler, S. Willitsch, E. Yurtsever, T. González-Lezana and P. Villarreal,
“N2+ (2Σ+g) and Rb(2S) in a hybrid trap: Modeling ion losses from radiative association paths"
I. Rouse and S. Willitsch,
"The energy distribution of an ion in a radiofrequency trap interacting with a nonuniform neutral buffer gas"
D. Haas, C. von Planta, Th. Kierspel, D. Zhang and S. Willitsch,
“Long-term trapping of Stark-decelerated molecules"
U. Rivero, O. T. Unke, M. Meuwly and S. Willitsch,
"Reactive Atomistic Simulations of Diels-Alder Reactions: the Importance of Molecular Rotations"
J. Chem. Phys. 151 (2019), 104301 (arXiv 1906.07455) (supporting data at 10.5281/zenodo.3291502)
A. D. Dörfler, P. Eberle, D. Koner, M. Tomza, M. Meuwly and S. Willitsch,
"Long-range vs. short-range effects in cold molecular ion-neutral collisions: Charge exchange of Rb with N2+ and O2+"
Nat. Commun. 10 (2019), 5429 (arXiv 1906.12285) (supporting data at https://zenodo.org/records/3701315)
Z. Meir, D. Zhang and S. Willitsch,
“Cold molecules: techniques and applications"
A. Kilaj, H. Gao, D. Rösch, U. Rivero, J. Küpper and S. Willitsch
"Observation of different reactivities of para- and ortho-water towards trapped diazenylium ions"
I. Rouse and S. Willitsch,
"Energy distributions of an ion in a radiofrequency trap immersed in a buffer gas under the influence of additional external forces"
D. Haas, S. Scherb, D. Zhang and S. Willitsch,
"Optimizing the density of Stark decelerated radicals at low final velocities: a tutorial review"
S. Schlemmer, S. Willitsch and T. Steimle,
"Introduction to the special issue on molecular spectroscopy in traps"
I. Rouse and S. Willitsch,
"Superstatistical energy distributions of an ion in an ultracold buffer gas"
U. Rivero, M. Meuwly and S. Willitsch,
"A Computational Study of the Diels-Alder Reactions Between 2,3-Dibromo-1,3-Butadiene and Maleic Anhydride"
D. Zhang and S. Willitsch,
"Cold ion chemistry"
S. Willitsch,
"Chemistry with controlled ions"
O. Dulieu and S. Willitsch,
"Ion Coulomb crystals: From quantum technology to chemistry close to the absolute zero point"
D. Rösch und S. Willitsch,
"Spektroskopie und Chemie mit kalten Ionen"
A. Mokhberi, R. Schmeid and S. Willitsch,
"Optimised surface-electrode ion-trap junctions for experiments with cold molecular ions"
P. Eberle, A. D. Dörfler, C. von Planta, K.Ravi and S.Willitsch,
"A dynamic ion-atom hybrid trap for high-resolution cold-collision studies ”
Daniel Rösch, Hong Gao, Ardita Kilaj and Stefan Willitsch,
"Design and characterization of a linear quadrupole ion trap for high-resolution Coulomb-crystal time-of-flight mass spectrometry”
M. Germann and S. Willitsch,
"Fine- and hyperfine-structure effects in molecular photoionization: I. General theory and direct photoionization”
M. Germann and S. Willitsch,
"Fine- and hyperfine-structure effects in molecular photoionization: II. Resonance-enhanced multiphoton ionization and hyperfine-selective generation of molecular cations”
L. Ploenes, D. Haas, D. Zhang, S. Y. T. van de Meerakker and S. Willitsch,
"Cold and intense OH radical beam sources”
M. Germann and S. Willitsch,
"Line strengths for fine- and hyperfine-resolved electric-quadrupole rotation-vibration transitions in Hund’s case b molecules”
I. Rouse and S. Willitsch,
"Superstatistical velocity distributions of cold trapped ions in molecular dynamics simulations"
P. Eberle, A.D. Dörfler, C. von Planta, R. Krishnamurthy, D. Haas, D. Zhang, S.Y. T. van de Meerakker and S. Willitsch,
"Ion-Atom and Ion-Molecule Hybrid Systems: Ion-Neutral Chemistry at Ultralow Energies"
S. Willitsch,
"Ion-atom hybrid systems"
O. Dulieu and S. Willitsch,
“Cristaux coulombiens: De la technologie quantique à la chimie proche du zéro absolu”
M. Germann, X. Tong and S. Willitsch,
"Forbidden Vibrational Transitions in Cold Molecular Ions: Experimental Observation and Potential Applications"
A. Mokhberi and S. Willitsch,
"Structural and energetic properties of molecular Coulomb crystals in a surface-electrode ion trap"
New J. Phys. 17, 045008 (2015) invited for the Focus on New Frontiers of Cold Molecules Research
M. Germann, X. Tong and S. Willitsch,
“Observation of electric-dipole-forbidden infrared transitions in cold molecular ions”
A. Mokhberi and S. Willitsch;
"Sympathetic cooling of molecular ions in a surface-electrode ion trap”
D. Rösch, S. Willitsch, Y.-P. Chang, J. Küpper;
"Chemical reactions of conformationally selected 3-aminophenol molecules in a beam with Coulomb-crystallized Ca+ ions”
Y.-P. Chang, K. Dlugolecki, J. Küpper, D. Rösch, D. Wild, S. Willitsch;
"Specific Chemical Reactivities of Spatially Separated 3-Aminophenol Conformers with Cold Ca+ Ions"
Corresponding perspective by Michael C. Heaven:
“Turn the Molecule This Way for a Faster Reaction”
S. Willitsch;
"Ultracold ménage a trois"
Felix H. J. Hall, Pascal Eberle, Gregor Hegi, Maurice Raoult, Mireille Aymar, Olivier Dulieu, and Stefan Willitsch;
"Ion-neutral chemistry at ultralow energies: Dynamics of reactive collisions between laser-cooled Ca+ ions and Rb atoms in an ion-atom hybrid trap",
Felix H. J. Hall, Mireille Aymar, Maurice Raoult, Olivier Dulieu, and Stefan Willitsch;
"Light-Assisted Cold Chemical Reactions of Barium Ions with Rubidium Atoms",
Felix H. J. Hall and Stefan Willitsch;
"Millikelvin Reactive Collisions between Sympathetically-Cooled Molecular Ions and Laser-Cooled Atoms in an Ion-Atom Hybrid Trap"
Xin Tong, Tibor Nagy, Juvenal Yosa Reyes, Matthias Germann, Markus Meuwly, Stefan Willitsch;
"State-selected ion-molecule reactions with Coulomb-crystallized molecular ions in traps",
Chem. Phys. Lett. 547 1-8 (2012) (Frontiers and cover article)
J. Mur-Petit, J. Perez-Rios, J. Campos-Martinez, M. I. Hernandez, S. Willitsch, and J. J. Garcia-Ripoll;
"Towards a Molecular Ion Qubit"
"Advances in Atom and Molecule Machines”, Vol. 2, Springer 2012
Jordi Mur-Petit, Juan Jose Garcıa-Ripoll, Jesus Perez-Rios, Jose Campos-Martinez, Marta I. Hernandez, and Stefan Willitsch;
“Temperature-independent quantum logic for molecular spectroscopy”,
Stefan Willitsch;
“Coulomb-crystallised molecular ions in traps: methods, applications, prospects”
Olivier Dulieu, Roman Krems, Matthias Weidemüller and Stefan Willitsch,
“Physics and Chemistry of Cold Molecules”
Felix H.J. Hall, Mireille Aymar, Nadia Bouloufa, Olivier Dulieu, and Stefan Willitsch,
“Light-assisted ion-neutral reactive processes in the cold regime: radiative molecule formation vs. charge exchange”,
I.M. Georgescu and S. Willitsch,
"Theoretical characterization of laser- and sympathetically-cooled ions in surface-electrode ion traps "
X. Tong, D. Wild and S. Willitsch,
“Collisional and radiative effects in the state-selective preparation of translationally cold molecular ions in ion traps”
S. Willitsch,
“Experimental methods in cation spectroscopy”
p. 1691 in Handbook of High-Resolution Spectroscopies, ed. M. Quack and F. Merkt, Wiley 2011
F. Merkt, S. Willitsch and U. Hollenstein,
“High-resolution photoelectron spectroscopy”
p. 1617 in Handbook of High-Resolution Spectroscopies, ed. M. Quack and F. Merkt, Wiley 2011