Time- and phase-resolved emulation of sign-selective counterdiabatic dynamics in a superconducting qutrit

In cyclic three-level systems, phase-sensitive interference can convert a coupling-sign reversal into a population contrast, providing a controllable analog of handedness. We emulate this mechanism in a superconducting transmon qutrit using two resonant single-photon drives and a phase-controlled effective two-photon drive. Effective-loop phases ΦL = +π/2 and ΦR = −π/2, separated by π, reverse the auxiliary contribution to the dark–bright coupling, canceling the intrinsic nonadiabatic term for L and reinforcing it for R. Time-resolved trajectories reveal dark-pathway transfer for L and bright-manifold participation for R. Measured late-time averages give a target-state population contrast of 0.929. Loop-phase measurements establish phase selectivity, while pulse-area and common-mode amplitude scans characterize the operating regime and control sensitivity. These results provide direct time- and phase-domain access to sign-selective counterdiabatic interference in a programmable cyclic qutrit.