2017

2015

2014

2012



2011

  • R. M. W. van Bijnen, S. Smit, K. A. H. van Leeuwen, E. J. D. Vredenbregt, S. J. J. M. F. Kokkelmans, Adiabatic Formation of Rydberg Crystals with Chirped Laser Pulses, J. Phys. B: At. Mol. Opt. Phys. 44 184008 (2011).

  • Jacobus Portegies and Servaas Kokkelmans, Efimov Trimers in a Harmonic Potential, Few-Body Syst. 51, 219 (2011).

  • L. B. Taylor, R. M. W. van Bijnen, D. H. J. O'Dell, N. G. Parker, S. J. J. M. F. Kokkelmans, and A. M. Martin, Synthetic magneto-hydrodynamics in Bose-Einstein condensates and routes to vortex nucleation, Phys. Rev A 84, 021604(R) (2011).

  • Noam Gross, Zav Shotan, Olga Machtey, Servaas Kokkelmans, and Lev Khaykovich, Study of Efimov physics in two nuclear-spin sublevels of 7Li, C. R. Physique 12, 4 (2011)

2010

  • M.R. Goosen, T.G. Tiecke, W. Vassen, and S.J.J.M.F. Kokkelmans, Feshbach resonances in 3He*-4He* mixtures, Phys. Rev. A 82, 042713 (2010).

  • T.G. Tiecke, M.R. Goosen, J.T.M. Walraven, and S.J.J.M.F. Kokkelmans, Asymptotic Bound-state Model for Feshbach Resonances, Phys. Rev. A 82, 042712 (2010).

  • Noam Gross, Zav Shotan, Servaas Kokkelmans, and Lev Khaykovich, Evidence for spin independent short-range three-body physics in ultracold atoms, Phys. Rev. Lett. 105, 103203 (2010).

  • R. M. W. van Bijnen, N. G. Parker, S. J. J. M. F. Kokkelmans, A. M. Martin, and D. H. J. O'Dell, Collective excitation frequencies and stationary states of trapped dipolar Bose-Einstein condensates in the Thomas-Fermi regime, Phys. Rev. A 82, 033612 (2010).

  • T.G. Tiecke, M.R. Goosen, A. Ludewig, S.D. Gensemer, S. Kraft, S.J.J.M.F. Kokkelmans, and J.T.M. Walraven, Search for broad Feshbach resonances in the 6Li-40K mixture, Phys. Rev. Lett. 104, 053202 (2010).



2009

  • Noam Gross, Zav Shotan, Servaas Kokkelmans, and Lev Khaykovich, Observation of universality in ultracold 7Li three-body recombination, Phys. Rev. Lett. 103, 163202 (2009).

  • B. J. Verhaar, E. G. M. van Kempen, and S. J. J. M. F. Kokkelmans, Predicting scattering properties of ultracold atoms: Adiabatic accumulated phase method and mass scaling, Phys. Rev. A 79, 032711 (2009).

  • Johan Mentink and Servaas Kokkelmans, Two interacting atoms in an optical lattice site with anharmonic terms, Phys. Rev. A 79, 032709 (2009).

2008

  • S. G. Bhongale, S. J. J. M. F. Kokkelmans, and Ivan H. Deutsch, Analytic models of ultra-cold atomic collisions at negative energies for application to confinement-induced resonances, Phys. Rev. A 77, 052702 (2008).

  • Bout Marcelis, Boudewijn Verhaar, and Servaas Kokkelmans, Total control over ultracold interactions via electric and magnetic fields, Phys. Rev. Lett. 100, 153201 (2008).

  • B. Marcelis, S.J.J.M.F. Kokkelmans, G.V. Shlyapnikov, and D.S. Petrov, Collisional properties of weakly bound heteronuclear dimers, Phys. Rev. A 77, 032707 (2008).

  • E. Wille, F.M. Spiegelhalder, G. Kerner, D. Naik, A. Trenkwalder, G. Hendl, F. Schreck, R. Grimm, T.G. Tiecke, J.T.M. Walraven, S.J.J.M.F. Kokkelmans, E. Tiesinga, P.S. Julienne, Exploring an ultracold Fermi-Fermi mixture: Interspecies Feshbach resonances and scattering properties of 6Li and 40K, Phys. Rev. Lett. 100, 053201 (2008).

  • Steven Gensemer, Russel Hart, Ross Martin, Xinye Xu, Ronald Legere, Kurt Gibble, and Servaas Kokkelmans, Precise Measurements of s-wave scattering phase shifts with a juggling atomic clock,.Frequency Standards and Metrology: Proceedings of the 7th Symposium‎



2007

  • S. G. Bhongale, M. R. Goosen, and S.J.J.M.F. Kokkelmans, BCS-BEC crossover in a strongly correlated Fermi gas, arXiv:0710.5288.



2006

  • S. G. Bhongale and S. J. J. M. F. Kokkelmans, BCS-BEC Crossover in the Strongly Correlated Regime of ultra-cold Fermi gases, cond-mat/0607782.

  • Bout Marcelis and Servaas Kokkelmans: Fermionic superfluidity with positive scattering length, Phys. Rev. A 74, 023606 (2006).



2005

  • Stephan Dürr, Thomas Volz, Niels Syassen, Gerhard Rempe, Eric van Kempen, Servaas Kokkelmans, Boudewijn Verhaar, Harald Friedrich: Dissociation of Feshbach Molecules into Different Partial Waves, Phys. Rev. A 72, 052707 (2005).

  • T. Volz, S. Dürr, N. Syassen, G. Rempe, E. van Kempen, and S. Kokkelmans: Feshbach spectroscopy of a shape resonance, Phys. Rev. A 72, 010704 (2005).

  • F. Chevy, E.G.M. Van Kempen, T. Bourdel, J. Zhang, L. Khaykovich, M. Teichmann, L. Tarruell, S.J.J.M.F. Kokkelmans, C. Salomon: Resonant scattering properties close to a p-wave Feshbach resonance, Phys. Rev. A 71, 062710 (2005).

  • S. De Palo, M. L. Chiofalo, M. J. Holland, S. J. J. M. F. Kokkelmans: Superfluidity of an atomic Fermi gas near the unitarity limit, Laser Physics 15 (2), 376 (2005).

  • J. Zhang, E.G.M. Van Kempen, T. Bourdel, L. Khaykovich, J. Cubizolles, F. Chevy, M. Teichmann, L. Tarruell, S.J.J.M.F. Kokkelmans, C. Salomon: Expansion of a lithium gas in the BEC-BCS crossover, AIP Conf. Proc. (Atomic Physics 19) 700, 228 (2005). (see also cond-mat/0410167)



2004

  • H. Marion, S. Bize, L. Cacciapuoti, D. Chambon, F. Pereira Dos Santos, G. Santarelli, P. Wolf, A. Clairon, A. Luiten, M. Tobar, S. Kokkelmans, C. Salomon: First observation of feshbach resonances at very low magnetic field in a 133Cs fountain, Proc. of the 2004 European Frequency and Time Forum (2004) (see also physics/0407064).

  • E.G.M. v. Kempen, B. Marcelis, S.J.J.M.F. Kokkelmans: Formation of fermionic molecules via interisotope Feshbach resonances, Phys. Rev. A 70, 012701 (2004).

  • J. Zhang, E.G.M. Van Kempen, T. Bourdel, L. Khaykovich, J. Cubizolles, F. Chevy, M. Teichmann, L. Tarruell, S.J.J.M.F. Kokkelmans, C. Salomon: P-wave Feshbach resonances of ultra-cold 6Li, Phys. Rev. A 70, 030702 (2004).

  • S. De Palo, M. L. Chiofalo, M. J. Holland, S. J. J. M. F. Kokkelmans: Resonance effects on the crossover of bosonic to fermionic superfluidity, Physics Letters A 327, 490 (2004).

  • T. Bourdel, L. Khaykovich, J Cubizolles, J. Zhang, F. Chevy, M. Teichmann, L. Tarruell, S.J.J.M.F. Kokkelmans, C. Salomon: Experimental Study of the BEC-BCS Crossover Region in Lithium 6, Phys. Rev. Lett. 93, 050401 (2004).

  • B. Marcelis, E. G. M. van Kempen, B. J. Verhaar, S. J. J. M. F. Kokkelmans: Feshbach resonances with large background scattering length: interplay with open-channel resonances, Phys. Rev. A 70, 012701 (2004).

  • S. J. J. M. F. Kokkelmans, G. V. Shlyapnikov, and C. Salomon: Degenerate atom-molecule mixture in a cold Fermi gas, Phys. Rev. A 69, 031602 (2004).



2003

  • J. Cubizolles, T. Bourdel, S. J. J. M. F. Kokkelmans, G. V. Shlyapnikov, and C. Salomon: Production of Long-Lived Ultracold Li2 Molecules from a Fermi Gas, Phys. Rev. Lett. 91, 240401 (2003).

  • T. Bourdel, J. Cubizolles, L. Khaykovich, K. M. F. Magalhães, S. J. J. M. F. Kokkelmans, G. V. Shlyapnikov, and C. Salomon: Measurement of the Interaction Energy near a Feshbach Resonance in a Li Fermi Gas, Phys. Rev. Lett. 91, 020402 (2003).

  • N.R. Claussen, S.J.J.M.F. Kokkelmans, S.T. Thompson, E.A. Donley, and C.E. Wieman: Very high precision bound state spectroscopy near a 85Rb Feshbach resonance, Phys. Rev. Lett., Phys. Rev. A 67, 060701 (2003).



2002

  • S.J.J.M.F. Kokkelmans and M.J. Holland: Ramsey fringes in a Bose-Einstein condensate between atoms and Molecules, Phys. Rev. Lett. 89, 180401 (2002).

  • J.N. Milstein, S.J.J.M.F. Kokkelmans, and M.J. Holland: Resonance theory of the crossover from Bardeen-Cooper-Schrieffer superfluidity to Bose-Einstein condensation in a dilute Fermi gas, Phys. Rev. A 66, 043604 (2002).

  • S.J.J.M.F. Kokkelmans, J.N. Milstein, M.L. Chiofalo, R. Walser, and M.J. Holland: Resonance superfluidity: Renormalization of resonance scattering theory, Phys. Rev. A 65, 043604 (2002).

  • E.G.M. van Kempen, S.J.J.M.F. Kokkelmans, D.J. Heinzen, and B.J. Verhaar: Inter-isotope determination of ultracold rubidium interactions from three high-precision experiments, Phys. Rev. Lett. 88, 093201 (2002).

  • M.L. Chiofalo, S.J.J.M.F. Kokkelmans, J.N. Milstein, and M.J. Holland: Signatures of resonance superfluidity in a quantum Fermi gas, Phys. Rev. Lett. 88, 090402 (2002).

  • S.J.J.M.F. Kokkelmans, M. Holland, R. Walser, and M.L. Chiofalo: Resonance superfluidity in a quantum degenerate Fermi gas, Proceedings ICOLS 2001, Snowbird, Utah, USA (World Scientific, 2002).

  • S.J.J.M.F. Kokkelmans, M. Holland, M. Chiofalo, and R. Walser: Resonance superfluidity in a quantum degenerate Fermi gas, Acta Physica Polonica A 101, 387 (2002).



2001



2000



1999



1998



1997

  • S. Op de Beek, J.P.J. Driessen, S.J.J.M.F. Kokkelmans, W. Boom, H.C.W. Beijerinck, and B.J. Verhaar: Ionization widths for Ne(3l)-Ar systems (l = s,p): Application to ionization and intramultiplet mixing cross sections, Phys. Rev. A 56, 2792 (1997).

  • S.J.J.M.F. Kokkelmans and B.J. Verhaar: Discrepancies in experiments with cold hydrogen atoms, Phys. Rev. A 56, 4038 (1997).

  • S.J.J.M.F. Kokkelmans, B.J. Verhaar, K. Gibble, and D.J. Heinzen: Predictions for laser-cooled Rb clocks, Phys. Rev. A 56, R4389 (1997).

  • J.M. Vogels, C.C. Tsai, R.S. Freeland, S.J.J.M.F. Kokkelmans, B.J. Verhaar, and D.J. Heinzen: Prediction of Feshbach resonances in collisions of ultracold rubidium atoms, Phys. Rev. A 56, R1067 (1997).

  • S.J.J.M.F. Kokkelmans, H.M.J.M. Boesten, and B.J. Verhaar: Role of collisions in creation of overlapping Bose condensates, Phys. Rev. A 55, R1589 (1997).

Latest News:

Trapped electrons in the quantum degenerate regime

A full strength Coulomb interaction between trapped electrons can be felt only in absence of a neutralizing background. In order to study quantum degenerate electrons without such a background, an external trap is needed to compensate for the strong electronic repulsion. As a basic model for such a system, we study a trapped electron pair in a harmonic trap with an explicit inclusion of its Coulomb interaction. We find the eigenenergies of the system for any value of the trapping strength. The problem is solved either numerically or by using approximate methods. As function of the trapping strength a crossover can be made from the strongly to the weakly-coupled regime, and we show that in both regimes perturbative methods based on a pair-wise electron description would be effective for a many-particle trapped electron system.   arXiv:1508.00365

Stability of triplet rubidium ground-state molecules

Experiments involving ultracold molecules require sufficiently long lifetimes, which can be very short for excited rovibrational states in the molecular potentials. For alkali atoms such as rubidium, molecular, rovibrational ground-states can both be found in the electronic singlet and triplet configurations. The molecular singlet ground state is absolutely stable, however, the triplet ground state can decay to a deeper bound singlet molecule due to a radiative decay mechanism that involves the interatomic spin-orbit interaction. We investigate this mechanism, and find the lifetime of rubidium molecules in the triplet rovibrational ground-state to be about 13 minutes. This is sufficiently long for experimental purposes.   arXiv:1412.5799