  We introduce and analyze a dispersive qubit readout scheme where two-mode
squeezing is generated directly in the measurement cavities. The resulting
suppression of noise enables fast, high- fidelity readout of naturally weakly
coupled qubits, and the possibility to protect strongly coupled qubits from
decoherence by weakening their coupling. Unlike other approaches exploiting
squeezing, our setup avoids the difficult task of transporting and injecting
with high fidelity an externally-generated squeezed state. Our setup is also
surprisingly robust against unwanted non-QND backaction effects, as
interference naturally suppresses Purcell decay: the system acts as its own
Purcell filter. Our setup is compatible with the experimental state-of-the-art
in circuit QED systems, but the basic idea could also be realized in other
systems.
