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arXiv · 2601.00078

Double-Pumped Kerr Parametric Amplifier Beyond the Gain-Bandwidth Limit

Nicolas Zapata·Najmeh Etehadi Abari·Mitchell Field·Patrick Winkel·Simon Geisert·Soeren Ihssen·Anja Metelmann·Ioan M. Pop
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Abstract

Superconducting standing$-$wave parametric amplifiers are crucial for the readout of microwave quantum devices. Despite significant improvements in recent years, the need to operate near an instability point imposes a fundamental constraint: the instantaneous bandwidth decreases with increasing amplifier gain. Here we show that it is possible to obtain parametric amplification without instability by using two simultaneous drives that activate phase-preserving gain and frequency conversion. Realized in a granular aluminum dimer with Kerr nonlinearity, our method demonstrates a sixfold bandwidth increase at 20 dB gain, surpasses the conventional gain$-$bandwidth scaling up to 25 dB, and remains near the quantum limit.

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Nicolas Zapata, Najmeh Etehadi Abari, Mitchell Field, Patrick Winkel, Simon Geisert, Soeren Ihssen, Anja Metelmann, Ioan M. Pop. 2025-12-31. Double-Pumped Kerr Parametric Amplifier Beyond the Gain-Bandwidth Limit. https://arxiv.org/abs/2601.00078

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