Quantum dynamics of an atomic double-well system interacting with a trapped ion

We theoretically analyze the dynamics of an atomic double-well system with a single ion trapped in its center. We find that the atomic tunnelling rate between the wells depends both on the spin of the ion via the short-range spin-dependent atom-ion scattering length and on its motional state with tunnelling rates reaching hundreds of Hz. A protocol is presented that could transport an atom from one well to the other depending on the motional (Fock) state of the ion within a few ms. This phonon-atom coupling is of interest for creating atom-ion entangled states and may form a building block in constructing a hybrid atom-ion quantum simulator. We also analyze the effect of imperfect ground state cooling of the ion and the role of micromotion when the ion is trapped in a Paul trap. Due to the strong non-linearities in the atom-ion interaction, the micromotion can cause couplings to high energy atom-ion scattering states, preventing accurate state preparation and complicating the double-well dynamics. We conclude that the effects of micromotion can be reduced by choosing ion/atom combinations with a large mass ratio and by choosing large inter-well distances. The proposed double-well system may be realised in an experiment by combining either optical traps or magnetic microtraps for atoms with ion trapping technology.Comment: 14 pages, 13 figure

Bibliometric analyses on repository contents as a library service for the evaluation of research

Since the last two decennia, the library of Wageningen University and Research (or Wageningen UR) has been involved in several bibliometric analyses for the evaluation of scientific output of staff, chair groups, research institutes and graduate schools. In these bibliometric analyses several indicator scores, such as the number of publications, number of citations and citation impacts, are calculated. However, since publication and citation habits differ considerably per scientific discipline, indicator scores need to be standardized in order to make comparison of scientific outputs from staff, chair groups, research institutes or graduate schools, that belong to different scientific disciplines, possible. It is for this reason that Wageningen UR Library bases its bibliometric analyses on indicator scores that are standardized against average trend (or baseline) scores per research field. For the collection of scientific output that is subjected to bibliometric analyses the repository Wageningen Yield (WaY) is used. This repository contains metadata and links to scientific output of the staff, research groups, chair groups and institutes of Wageningen UR and is developed and managed by Wageningen UR Library. By the application of a link between the metadata of publications in WaY and citation scores in Thomson Reuters’ Web of Science, custom-made analyses can be performed efficiently. Usings the repository WaY as a source for Wageningen UR’s scientific output enables optimal use of meta data (e.g. affiliations of authors), improvement of completeness and data quality as well as awareness of library services. Moreover, the bibliometric analyses give insights in steps that can be taken to improve publication strategies for Wageningen UR staff, chair groups, research institutes and graduate schools

Temperature dependence of spin-cluster resonance intensity in RbFeCl3·2H2O

The spin-cluster resonance intensity is observed as a function of temperature in the pseudo-one-dimensional canted Ising metamagnet RbFeCl3·2H2O. For T 0.7 TN a pure one-dimensional Ising model gives a good description of the observed intensities. For T TN the intensity decreases rapidly as a function of temperature due to the destruction of the local ordering around a spin-cluster. The measured value of the intrachain interaction Ja/k of -36 K is in good agreement with earlier measurements on spin-cluster excitations

Mixed Mimetic Spectral Element method applied to Darcy's problem

We present a discretization for Darcy's problem using the recently developed Mimetic Spectral Element Method. The gist lies in the exact discrete representation of integral relations. In this paper, an anisotropic flow through a porous medium is considered and a discretization of a full permeability tensor is presented. The performance of the method is evaluated on standard test problems, converging at the same rate as the best possible approximation

High quality YBa2Cu3Ox ultra-thin films and Y/Pr/Y multilayers made by a modified RF-magnetron sputtering technique

High quality ĉ-axis oriented thin and ultra-thin films have been grown in situ on (100) surfaces of ZrO2, SrTiO3 and MgO. Sharp transitions were observed with Tc,zero of 87–91 K for films thicker than 70 Å. On atomically polished MgO substrates films as thin as 15 Å revealed a full transition to superconductivity above 45.5 K. The critical current density at 77 K was found to be strongly dependent on film thickness. A maximum value was found for a 100 Å film with 8 × 106A/cm2 at 77 K. Also, YBCO/PBCO/YBCO multilayer thin films have been fabricated in situ by the same technique. The epitaxy is maintained throughout the whole multilayer system. The superconducting properties of YBa2Cu3Ox layers do not change compared to single layers. Interdiffusion and possible chemical reaction close to the interfaces can be neglected.\ud \u

Controlled preparation of all high-Tc SNS-type edge junctions and DC SQUIDs

High-Tc SNS-type Josephson junctions and DC SQUIDs were successfully fabricated using hetero-epitaxially grown multilayers of YBa2Cu3Ox and PrBa2Cu3Ox. These layers are c-axis oriented and hence edges of the multilayers give rise to a current flow in the ab-plane between the electrodes of a Josephson junction. The necessary structuring was done by Ar ion beam etching. The individual junctions exhibit a supercurrent up to 80 K. The IcRn-product of these junctions usually has a lower limit of 8 mV at 4.2 K. Voltage modulation of the first DC SQUIDs can be observed up to 66 K. Details on the fabrication and measurements are presented

Relaxation phenomena in CsCoCl3·2 H2O

Dynamic susceptibility measurements have been performed on a single crystal of CsCoCl3·2H2O at liquid temperatures by means of a Hartshorn mutual inductance bridge. At the magnetic phase transition a maximum in τabs(H) has been observed. A jump in τabs(T) has been found at the λ-point of liquid helium