Quantum-droplet interferometry

We propose atom interferometers based on quantum droplet (QD), which is also being reported as a superior platform for interferometry. The emphasis has been given to harmonic-oscillator (HO) or ring-shaped potentials. In the HO trap, a Gaussian barrier induces coherent splitting; in the ring, one or two barriers guide the splitting and subsequent recombination. The atom number and relative mean-field interaction strength critically affect the interferometric performance. The transmission-coefficient analysis identifies values of the barrier parameters for the balanced $50:50$ splitting. The post-recombination atom-number imbalance serves as a sensitive indicator of the relative phase between merging daughter QDs. We demonstrate that the HO-based setup may serve as a tilt-meter and target detector, and the ring geometry may be used as a compact QD Sagnac interferometer for rotation sensing.