An Atomtronic Flux Qubit: A ring lattice of Bose-Einstein condensates interrupted by three weak links

We study a physical system consisting of a Bose – Einstein condensate con fi ned to a ring shaped lattice potential interrupted by three weak links. The system is assumed to be driven by an effective fl ux piercing the ring lattice. By employing path integral techniques, we explore the effective quantum dynamics of the system in a pure quantum phase dynamics regime. Moreover, the effects of the density ’ s quantum fl uctuations are studied through exact diagonalization analysis of the spectroscopy of the Bose – Hubbard model. We demonstrate that a clear two-level system emerges by tuning the magnetic fl ux at degeneracy. The lattice con fi nement, platform for the condensate, is realized experimentally employing a spatial light modulator