Strongly detuning the readout resonator to about twelve times the transmon frequency exponentially suppresses multi-excitation resonances, giving 99.93% QND readout fidelity and 0.02% leakage.
Interferometric Purcell suppression of spontaneous emission in a superconducting qubit
1 Pith paper cite this work. Polarity classification is still indexing.
1
Pith paper citing it
abstract
In superconducting qubits, suppression of spontaneous emission is essential to achieve fast dispersive measurement and reset without sacrificing qubit lifetime. We show that resonator-mediated decay of the qubit mode to the feedline can be suppressed using destructive interference, where the readout resonator is coupled to the feedline at two points. This "interferometric Purcell filter" does not require dedicated filter components or impedance mismatch in the feedline, making it suitable for applications such as all-pass readout. We design and fabricate a device with the proposed scheme and demonstrate suppression of resonator-mediated decay that exceeds 2 orders of magnitude over a bandwidth of 400 MHz for a resonator linewidth of 13.8 MHz.
fields
quant-ph 1years
2025 1verdicts
CONDITIONAL 1representative citing papers
citing papers explorer
-
High-frequency readout free from transmon multi-excitation resonances
Strongly detuning the readout resonator to about twelve times the transmon frequency exponentially suppresses multi-excitation resonances, giving 99.93% QND readout fidelity and 0.02% leakage.