The Shapiro effect in atomchip-based bosonic Josephson junctions

We analyze the emergence of Shapiro resonances in tunnel-coupled-Einstein condensates, realizing a bosonic Josephson junction. Our analysis based on an experimentally relevant implementation using magnetic double potentials on an atomchip. In this configuration the potential bias(implementing the junction voltage) and the potential barrier (realizing the link) are intrinsically coupled. We show that the dynamically driven exhibits significantly enhanced Shapiro resonances which will facilitate observation. To describe the systems response to the dynamic drive compare a single-mode Gross-Pitaevskii (GP) description, an improved-mode (TM) model and the self-consistent multi-configurational time Hartree for Bosons (MCTDHB) method. We show that in the case of atom-atom interactions or strong driving, the spatial dynamics of involved modes have to be taken into account, and only the MCTDHB method reliable predictions.