Coherent adiabatic transport of atoms in radio-frequency traps

Coherent transport by adiabatic passage has recently been suggested as a high-fidelity technique to engineer the centre-of-mass state of single atoms in inhomogenous environments. While the basic theory behind this process is well understood, several conceptual challenges for its experimental observation have still to be addressed. One of these is the difficulty that currently available optical or magnetic micro-trap systems have in adjusting the tunneling rate time-dependently while keeping resonance between the asymptotic trapping states at all times. Here we suggest that both requirements can be fulfilled to a very high degree in an experimentally realistic setup based on radio frequency traps on atom chips. We show that operations with close to 100% fidelity can be achieved and that these systems also allow significant improvements for performing adiabatic passage with interacting atomic clouds.

Using adiabatic coupling techniques in atom-chip waveguide structures

Adiabatic techniques are well known tools in multi-level electron systems to transfer population between different states with high fidelity. Recently it has been realised that these ideas can also be used in ultra-cold atom systems to achieve coherent manipulation of the atomic centre-of-mass states. Here we present an investigation into a realistic setup using three atomic waveguides created on top of an atom chip and show that such systems hold large potential for the observation of adiabatic phenomena in experiments.