Using vortices to probe Bose-Einstein condensate flow

We present a model for probing the flow of a Bose-Einstein condensate (BEC) trapped in a double-target potential. A target potential BEC contains a disk-shaped condensate surrounded by a ring condensate. A double-target BEC consists of two overlapping target BECs. Flow can be induced in one ring of the double-target BEC and will persist in that ring if left undisturbed. When a barrier potential is applied in the overlap region it is possible for this flow to transfer to the other ring. The mechanism for this transfer can be probed by imprinting a small vortex at a point along the mid-track of one of the rings and following its motion. We have generalized the model of vortex motion, described in Groszek, et al (PRA 97, 023617 (2018),) to model vortex motion as described by the rotatining-frame Gross-Pitaevskii equation (RFGPE) and applied this model to the double-target BEC. We describe this model and use it to try to understand the mechanism for flow transfer in double-target BECs and explain how this can be used to design a double-target BEC rotation sensor.