arXiv subjects

T. Matthey

Publications and source records attributed to T. Matthey.

3 recordsLinked to original sources

arXiv2006

Rf-induced persistent long-range ordered structures in two-species ion Coulomb crystals in a linear Paul trap

We report on the observations of three-dimensional long-range ordered structures in the central $^{40}$Ca$^+$ ion component of $^{40}$Ca$^+$--$^{44}$Ca$^+$ two-species ion Coulomb crystals in a linear Paul trap. In contrast to long-range ordering previously observed in single species crystals, the structures observed are strikingly persistent and always of one specific type in one particular orientation. Molecular dynamics simulations strongly indicate that these characteristics are a hitherto unpredicted consequence of the co-axial cylindrical symmetry of the central ion component of the Coulomb crystal and the radio frequency quadrupole trapping field.

physics.plasm-ph↗

arXiv2006

Observation of Three-dimensional Long-range Order in Smaller Ion Coulomb Crystals in an rf Trap

Three-dimensional long-range ordered structures in smaller and near-spherically symmetric Coulomb crystals of ^{40}Ca^+ ions confined in a linear rf Paul trap have been observed when the number of ions exceeds ~1000 ions. This result is unexpected from ground state molecular dynamics (MD) simulations, but found to be in agreement with MD simulations of metastable ion configurations. Previously, three-dimensional long-range ordered structures have only been reported in Penning traps in systems of ~50,000 ions or more.

physics.plasm-ph↗

arXiv2005

Quantum and Classical Calculations of Ground State Properties of Parabolic Quantum Dots

We report calculations for electronic ground states of parabolically confined quantum dots for up to 30 electrons based on the quantum Monte Carlo method. Effects of the electron-electron interaction and the response to a magnetic field are exposed. The wavefunctions and the ground state energies are compared with purely classical calculations performed with a comprehensive Molecular Dynamics code. For the chosen well parameters a close correspondence in the overall shape of electron density distribution is found even for small number of electrons, while the detailed radial distributions show the effects of Pauli principle in the quantal case.

cond-mat.str-el↗