Good news everyone! Our preprint Unifying Floquet theory of longitudinal and dispersive readout just got on the arxiv!!

Dispersive readout is the typical mechanism to determine the qubit state in cQED systems. Longitudinal readout, on the other hand, is less known but, potentially, can achieve higher readout fidelities in less time. Since dispersive readout is well-established, the theory on this mechanism is quite advanced compared to the theory on longitudinal readout. In this work, we develop a unifying framework for both mechanisms based on Floquet theory, which goes beyond any perturbative treatment, allowing us to capture both adibatic and non adiabatic regimes. We apply this theory to superconducting and spin qubits, showing great accuracy when compared to numerics.