aiqbench analysis
This study demonstrates a closed four-mode superconducting system that emulates parity-time dimer dynamics without engineered dissipation, achieving enhanced sensor sensitivity near an exceptional point. By utilizing parametric couplings in a coplanar-waveguide resonator, the research bypasses coherence limitations inherent to conventional gain-loss implementations while operating outside standard quantum limits. This advancement offers significant potential for high-precision sensing applications within non-Hermitian quantum architectures.
Enhanced Sensitivity near a Quantum Exceptional Point in the Absence of Engineered Dissipation
arXiv:2606.16060v1 Announce Type: new Abstract: Non-Hermitian systems exhibit phenomena absent from Hermitian systems, including exceptional points (EPs), at which two or more eigenvectors coalesce. Conventional implementations rely on gain and loss, which strongly limit quantum coherence. Here, following a proposal by Wang and Clerk (PRA 2019), we realize a closed four-mode quantum system that emulates the dynamics of a PT dimer - two coupled resonators with balanced gain and loss - without engineered dissipation. The four modes are implemented as harmonics of a superconducting coplanar-waveguide resonator, with parametric couplings engineered using a current-pumped SNAIL. We use this device as a sensor for small variations in the PT dimer coupling strength. From signal-to-noise-ratio measurements, we observe enhanced sensitivity near the EP in a non-quantum-limited regime.
Authors:Réouven Assouly, Harry Hanlim Kang, Aziza Almanakly, Michael A. Gingras, Bethany M. Niedzielski, Hannah Stickler, Mollie E. Schwartz, Kyle Serniak, Max Hays, Jeffrey A. Grover, William D. Oliver
Abstract:Non-Hermitian systems exhibit phenomena absent from Hermitian systems, including exceptional points (EPs), at which two or more eigenvectors coalesce. Conventional implementations rely on gain and loss, which strongly limit quantum coherence. Here, following a proposal by Wang and Clerk (PRA 2019), we realize a closed four-mode quantum system that emulates the dynamics of a PT dimer - two coupled resonators with balanced gain and loss - without engineered dissipation. The four modes are implemented as harmonics of a superconducting coplanar-waveguide resonator, with parametric couplings engineered using a current-pumped SNAIL. We use this device as a sensor for small variations in the PT dimer coupling strength. From signal-to-noise-ratio measurements, we observe enhanced sensitivity near the EP in a non-quantum-limited regime.
arXiv:2606.16060 [quant-ph]
(or arXiv:2606.16060v1 [quant-ph] for this version)
https://doi.org/10.48550/arXiv.2606.16060 arXiv-issued DOI via DataCite (pending registration)
Full text under the publisher's open licence · 162 words
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