aiqbench analysis
This study demonstrates a junction-free kinetic-inductance parametric amplifier operating at 23 GHz with added noise below 1.4 quanta, effectively bridging the gap for high-frequency superconducting quantum readout. By utilizing thin-film niobium nitride, the architecture achieves a 100 MHz gain-bandwidth product while maintaining performance near the quantum limit, enabling potential extensions to millimeter-wave regimes. These metrics are critical for advancing qubit coherence and expanding search windows for axion dark matter detection.
A K-band Kinetic Inductance Parametric Amplifier Near the Quantum Limit
arXiv:2606.08406v1 Announce Type: new Abstract: Advancing superconducting quantum devices to higher operating frequencies broadens their functionality and enables operation at elevated temperatures, but it also requires near-quantum-limited amplifiers beyond the few-gigahertz regime. Here we present a junction-free, kinetic-inductance parametric amplifier based on thin-film niobium nitride (NbN) operating at 23 GHz in the microwave K-band, achieving a gain up to 40 dB, a 100 MHz gain-bandwidth product, a 1 dB saturation input power of -85 dBm with 23 dB gain, and added noise no greater than 1.4 quanta for phase-preserving amplification. Leveraging the large superconducting gap of NbN, this architecture can be extended to even higher frequencies, supporting applications such as high-fidelity readout of millimeter-wave superconducting qubits and axion searches over an expanded mass window.
Abstract:Advancing superconducting quantum devices to higher operating frequencies broadens their functionality and enables operation at elevated temperatures, but it also requires near-quantum-limited amplifiers beyond the few-gigahertz regime. Here we present a junction-free, kinetic-inductance parametric amplifier based on thin-film niobium nitride (NbN) operating at 23 GHz in the microwave K-band, achieving a gain up to 40 dB, a 100 MHz gain-bandwidth product, a 1 dB saturation input power of -85 dBm with 23 dB gain, and added noise no greater than 1.4 quanta for phase-preserving amplification. Leveraging the large superconducting gap of NbN, this architecture can be extended to even higher frequencies, supporting applications such as high-fidelity readout of millimeter-wave superconducting qubits and axion searches over an expanded mass window.
arXiv:2606.08406 [quant-ph]
(or arXiv:2606.08406v1 [quant-ph] for this version)
https://doi.org/10.48550/arXiv.2606.08406 Focus to learn more arXiv-issued DOI via DataCite (pending registration)
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