Floquet-Engineered Dissipation via Pulsed Parametric Modulation

Parametric frequency modulation is a powerful tool for engineering effective interactions and controlled dissipation in superconducting qubits. When a qubit is modulated at an appropriate frequency, parametric resonance with a dissipative resonator leads to enhanced qubit decay. While continuous modulation is well understood through Bessel-function sidebands, the behavior under time-structured modulation remains largely unexplored. Here we present an experimental study of pulsed modulation with variable on/off durations and its impact on the dissipation of a tunable transmon qubit. We find that pulsed modulation dramatically reshapes frequency response of the dissipation, yielding a rich landscape of decay features. These results show how pulsed modulation can change the dissipative spectrum of a qubit, offering new ways to control open quantum dynamics.