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).

  • V. D. Snyder, S. J. J. M. F. Kokkelmans, and L. D. Carr, Hartree-Fock-Bogoliubov Model and Simulation of Attractive and Repulsive Bose-Einstein Condensates, arXiv:1102.2104

  • 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 EFTF (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:

Creation of Rydberg Crystals

Ultracold atomic gases have been used extensively in recent years to realize textbook examples of condensed matter phenomena. Recently, phase transitions to ordered structures have been predicted for gases of highly excited, 'frozen' Rydberg atoms. Such Rydberg crystals are a model for dilute metallic solids with tunable lattice parameters, and provide access to a wide variety of fundamental phenomena. We investigate theoretically how such structures can be created in four distinct cold atomic systems, by using tailored laser-excitation in the presence of strong Rydberg-Rydberg interactions. We study in detail the experimental requirements and limitations for these systems, and characterize the basic properties of small crystalline Rydberg structures in one, two and three dimensions: arXiv:1103.2096

Collapsing Bose-Einstein Condensates

We describe a model of dynamic Bose-Einstein condensates near a Feshbach resonance that is computationally feasible under assumptions of spherical or cylindrical symmetry. Simulations in spherical symmetry approximate the experimentally measured time to collapse of an unstably attractive condensate, suggesting that the quantum fluctuations and atom-molecule pairing included in the model are the dominant mechanisms during collapse. Simulations of condensates with repulsive interactions find some quantitative disagreement, suggesting that pairing and quantum fluctuations are not the only significant factors for condensate loss or burst formation. Inclusion of three-body recombination was found to be inconsequential in all of our simulations:  arXiv:1102.2104

Efimov Trimers in a Harmonic Potential

We study the Efimov effect in a harmonic oscillator in the hyperspherical formulation, and show how a reduced model allows for a description that is a generalization of the Efimov effect in free space and leads to results that are easily interpreted. Efimov physics may be observed by varying the value of the scattering length, since in the regime where the trimers have a mixed harmonic oscillator and Efimov character, the inelastic properties of these states are still manageable. The model also allows for the study of non-universal Efimov trimers by including the effective range scattering parameter. While we find that in a certain regime the effective range parameter can take over the role of the three-body parameter, interestingly, we obtain a numerical relationship between these two parameters different from what was found in other models:  arXiv:1101.0696

Synthetic hydrodynamics in Bose-Einstein condensates

Engineering of synthetic magnetic flux in Bose-Einstein condensates [Lin et al., Nature 462, 628 (2009)] has prospects for attaining the high vortex densities necessary to emulate the fractional quantum Hall effect. We analytically establish the hydrodynamical behaviour of a condensate in a uniform synthetic magnetic field, including its density and velocity profile. Importantly, we find that the onset of vortex nucleation observed experimentally corresponds to a dynamical instability in the hydrodynamical solutions and reveal other routes to instability and anticipated vortex nucleation. arXiv:1011.4315