Supplementary information for Fast Accurate State Measurement with Superconducting Qubits
نویسندگان
چکیده
where CF and VF are the filter capacitance and voltage amplitude. See Fig. 1(a). To compute the ratio Vq/VF we use voltage division. We make the crucial observation that to calculate the qubit damping we must analyze the circuit impedances at the qubit frequency. Because the qubit is off resonance from the measurement resonator, the measurement resonator’s impedance Zr is lower than the impedance Zg of the coupling capacitor Cg, ie. Zr Zg. Therefore with voltage Vq across the qubit, we have a current Ig = Vq/Zg flowing through Cg. By similar reasoning Zκ Zr, so most of the current QF Cκ Cg Ig Vq Vr VF
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