Quantum rotation sensing with a four-site integrable model
Joel Bacellar Neves
Abstract
In this work, we present a four-site integrable model that describes the interaction and tunneling of ultracold dipolar bosons trapped in a rotating, tetrahedral site arrangement. The model is derived from an extension of the Bose-Hubbard model in a rotating frame where the interaction and tunneling parameters have been appropriately selected to produce four independent and conserved quantities, establishing integrability. Two of these conserved quantities – related to the two nonzero circulation modes found in the system – are used to derive an effective Hamiltonian dynamically equivalent to the system for large interactions, allowing for the analytical prediction of its quantum dynamics. By analyzing the site population dynamics in this large interaction regime, we find that rotation induces population imbalance in a manner akin to the Sagnac effect. This is exploited to design a simple rotation sensing protocol capable of estimating reference frame rotation through population imbalance measurements. We calculate the sensitivity of the proposed protocol and demonstrate it has a scaling advantage due to a nontrivial manifestation of the system’s nonlinearity, enabled by integrability. The findings presented here open further investigations into the effects of rotation in multi-site integrable models, highlighting their great potential for modeling quantum devices and quantum sensors.