We note that in this particular circuit architecture, the direction of the circularly polarized light has no effect on the direction of exciton flux. The direction of exciton flux in the branched circuit is determined by the angles of the linear chromophores relative to the direction of light propagation. Therefore, switching between RCP and LCP light will not change the exciton flux in Fig. . This is analogous to observations that the AB effect does not manifest in open cycles. In fact, one can argue that circularly polarized light is not strictly necessary in this particular construct. A similar phase control could be achieved with a linear pulse on a circuit of chromophore molecules with precisely aligned dipole moment vectors. Indeed, the control of the phase is an artifact of the alignment between the molecules and does not necessarily arise for the complex phase in the coupling. We discuss this issue further in the SI.