@article{HenkelGardinerNegretti2004,
  author    = {Henkel, Carsten and Gardiner, Simon A. and Negretti, Antonio},
  title     = {(De)coherence physics with condensates in microtraps},
  issn      = {1054-660X},
  year      = {2004},
  abstract  = {We discuss the dynamics of a condensate in a miniaturized electromagnetic trap formed above a microstructured substrate. Recent experiments have found that trap lifetimes get reduced when approaching the substrate because atoms couple to thermally excited near fields. The data agree quantitatively with our theory [Appl. Phys. B 69, 379 (1999)]. We focus on the decoherence of a quantum degenerate gas in a quasi-one-dimensional trap. Monte Carlo simulations indicate that atom interactions reduce the condensate decoherence rate. This is explained by a simple theory in terms of the suppression of long-wavelength excitations. We present preliminary simulation results for the adiabatic generation of dark solitons},
  language  = {en}
}
@misc{HenkelSteaneKaiseretal.1994,
  author    = {Henkel, Carsten and Steane, Andrew M. and Kaiser, Robin and Dalibard, Jean},
  title     = {A modulated mirror for atomic interferometry},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-42279},
  year      = {1994},
  abstract  = {A novel atomic beam splitter, using reflection of atoms off an evanescent light wave, is investigated theoretically. The intensity or frequency of the light is modulated in order to create sidebands on the reflected de Broglie wave. The weights and phases of the various sidevands are calculated using three different approaches: the Born approximation, a semiclassical path integral approach, and a numerical solution of the time-dependent Schrdinger equation. We show how this modulated mirror could be used to build practical atomic interferometers.},
  language  = {en}
}
@article{ZuritaSanchezHenkel2012,
  author    = {Zurita-Sanchez, Jorge R. and Henkel, Carsten},
  title     = {Acoustic waves from mechanical impulses due to fluorescence resonant energy (Forster) transfer Blowing a whistle with light},
  series = {epl : a letters journal exploring the frontiers of physics},
  volume    = {97},
  journal   = {epl : a letters journal exploring the frontiers of physics},
  number    = {4},
  publisher = {EDP Sciences},
  address   = {Mulhouse},
  issn      = {0295-5075},
  doi       = {10.1209/0295-5075/97/43002},
  pages     = {6},
  year      = {2012},
  abstract  = {We present a momentum transfer mechanism mediated by electromagnetic fields that originates in a system of two nearby molecules: one excited (donor D*) and the other in ground state (acceptor A). An intermolecular force related to fluorescence resonant energy or Forster transfer (FRET) arises in the unstable D* A molecular system, which differs from the equilibrium van der Waals interaction. Due to the its finite lifetime, a mechanical impulse is imparted to the relative motion in the system. We analyze the FRET impulse when the molecules are embedded in free space and find that its magnitude can be much greater than the single recoil photon momentum, getting comparable with the thermal momentum (Maxwell-Boltzmann distribution) at room temperature. In addition, we propose that this FRET impulse can be exploited in the generation of acoustic waves inside a film containing layers of donor and acceptor molecules, when a picosecond laser pulse excites the donors. This acoustic transient is distinguishable from that produced by thermal stress due to laser absorption, and may therefore play a role in photoacoustic spectroscopy. The effect can be seen as exciting a vibrating system like a string or organ pipe with light; it may be used as an opto-mechanical transducer.},
  language  = {en}
}
@article{BoedeckerHenkel2003,
  author    = {Boedecker, Geesche and Henkel, Carsten},
  title     = {All-frequency effective medium theory of a photonic crystal},
  issn      = {1094-4087},
  year      = {2003},
  language  = {en}
}
@misc{HenkelCourtoisAspect1994,
  author    = {Henkel, Carsten and Courtois, Jean-Yves and Aspect, Alain},
  title     = {Atomic diffraction by a thin phase grating},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-42269},
  year      = {1994},
  abstract  = {We present a semiclassical perturbation method for the description of atomic diffraction by a weakly modulated potential. It proceeds in a way similar to the treatment of light diffraction by a thin phase grating, and consists in calculating the atomic wavefunction by means of action integrals along the classical trajectories of the atoms in the absence of the modulated part of the potential. The capabilities and the validity condition of the method are illustrated on the well-known case of atomic diffraction by a Gaussian standing wave. We prove that in this situation the perturbation method is equivalent to the Raman-Nath approximation, and we point out that the usually-considered Raman-Nath validity condition can lead to inaccuracies in the evaluation of the phases of the diffraction amplitudes. The method is also applied to the case of an evanescent wave reflection grating, and an analytical expression for the diffraction pattern at any incidence angle is obtained for the first time. Finally, the application of the method to other situations is briefly discussed.},
  language  = {en}
}
@article{SchiefeleHenkel2011,
  author    = {Schiefele, Juergen and Henkel, Carsten},
  title     = {Bosonic enhancement of spontaneous emission near an interface},
  series = {Modern physics letters : A, Particles and fields, gravitation, cosmology, nuclear physics},
  volume    = {375},
  journal   = {Modern physics letters : A, Particles and fields, gravitation, cosmology, nuclear physics},
  number    = {3},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0375-9601},
  doi       = {10.1016/j.physleta.2010.11.058},
  pages     = {680 -- 684},
  year      = {2011},
  abstract  = {We show how the spontaneous emission rate of an excited two-level atom placed in a trapped Bose-Einstein condensate of ground-state atoms is enhanced by bosonic stimulation. This stimulation depends on the overlap of the excited matter-wave packet with the macroscopically occupied condensate wave function, and provides a probe of the spatial coherence of the Bose gas. The effect can be used to amplify the distance-dependent decay rate of an excited atom near an interface.},
  language  = {en}
}
@article{SchiefeleHenkel2009,
  author    = {Schiefele, J{\"u}rgen and Henkel, Carsten},
  title     = {Casimir energy of a BEC : from moderate interactions to the ideal gas},
  issn      = {1751-8113},
  doi       = {10.1088/1751-8113/42/4/045401},
  year      = {2009},
  abstract  = {Considering the Casimir effect due to phononic excitations of a weakly interacting dilute Bose-Einstein condensate ( BEC), we derive a renormalized expression for the zero-temperature Casimir energy E-C of a BEC confined to a parallel plate geometry with periodic boundary conditions. Our expression is formally equivalent to the free energy of a bosonic field at finite temperature, with a nontrivial density of modes that we compute analytically. As a function of the interaction strength, E-C smoothly describes the transition from the weakly interacting Bogoliubov regime to the non- interacting ideal BEC. For the weakly interacting case, E-C reduces to leading order to the Casimir energy due to zero- point fluctuations of massless phonon modes. In the limit of an ideal Bose gas, our result correctly describes the Casimir energy going to zero.},
  language  = {en}
}
@article{HenkelJoulain2005,
  author    = {Henkel, Carsten and Joulain, Karl},
  title     = {Casimir force between designed materials : what is possible and what not},
  issn      = {0295-5075},
  year      = {2005},
  abstract  = {We establish strict upper limits for the Casimir interaction between multilayered structures of arbitrary dielectric or diamagnetic materials. We discuss the appearance of different power laws due to frequency-dependent material constants. Simple analytical expressions are in good agreement with numerical calculations based on Lifshitz theory. We discuss the improvements required for current ( meta) materials to achieve a repulsive Casimir force},
  language  = {en}
}
@article{IntravaiaHenkel2009,
  author    = {Intravaia, Francesco and Henkel, Carsten},
  title     = {Casimir interaction from magnetically coupled eddy currents},
  issn      = {0031-9007},
  doi       = {10.1103/Physrevlett.103.130405},
  year      = {2009},
  abstract  = {We study the quantum and thermal fluctuations of eddy (Foucault) currents in thick metallic plates. A Casimir interaction between two plates arises from the coupling via quasistatic magnetic fields. As a function of distance, the relevant eddy current modes cross over from a quantum to a thermal regime. These modes alone reproduce previously discussed thermal anomalies of the electromagnetic Casimir interaction between good conductors. In particular, they provide a physical picture for the Casimir entropy whose nonzero value at zero temperature arises from a correlated, glassy state.},
  language  = {en}
}
@article{PuhlmannHenkelHeueretal.2016,
  author    = {Puhlmann, Dirk and Henkel, Carsten and Heuer, Axel and Pieplow, Gregor and Menzel, Ralf},
  title     = {Characterization of a remote optical element with bi-photons},
  series = {Physica scripta : an international journal for experimental and theoretical physics},
  volume    = {91},
  journal   = {Physica scripta : an international journal for experimental and theoretical physics},
  publisher = {IOP Publ. Ltd.},
  address   = {Bristol},
  issn      = {0031-8949},
  doi       = {10.1088/0031-8949/91/2/023006},
  pages     = {113 -- 114},
  year      = {2016},
  abstract  = {We present a simple setup that exploits the interference of entangled photon pairs. 'Signal' photons are sent through a Mach-Zehnder-like interferometer, while 'idlers' are detected in a variable polarization state. Two-photon interference (in coincidence detection) is observed with very high contrast and for significant time delays between signal and idler detection events. This is explained by quantum erasure of the polarization tag and a delayed choice protocol involving a non-local virtual polarizer. The phase of the two-photon fringes is scanned by varying the path length in the signal beam or by rotating a birefringent crystal in the idler beam. We exploit this to characterize one beam splitter of the signal photon interferometer (reflection and transmission amplitudes including losses), using only information about coincidences and control parameters in the idler path. This is possible because our bi-photon state saturates the Greenberger-Yelin-Englert inequality between contrast and predictability.},
  language  = {en}
}