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arXiv · 2609.24533

Detection of signals in presence of noise through Josephson junction switching currents

O. V. Pountougnigni·R. Yamapi·C. Tchawoua·V. Pierro·G. Filatrella
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Abstract

Josephson junctions can be employed to reveal a sinusoidal signal in presence of Gaussian noise. To mimic realistic setups, the detection is performed linearly ramping the bias current until a switch to the finite voltage occurs; the analysis of the resulting switching currents can be exploited to decide about the presence of the harmonic drive. The signal is applied in two conditions: with an unknown initial phase (incoherent strategy) and with a known initial phase (coherent strategy). In both conditions, the analysis of the efficiency of the detection, performed through the signal-to-noise ratio, as estimated by the Kumar-Carrol index, shows that the dependence upon the Josephson junction ramp rate is beneficial, especially for relatively fast speed. One can conclude that the collection of the switching currents is a robust technique, and thus it is possible to exploit the advantages of a predetermined finite time to collect the data.

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O. V. Pountougnigni, R. Yamapi, C. Tchawoua, V. Pierro, G. Filatrella. 2026-09-21. Detection of signals in presence of noise through Josephson junction switching currents. https://doi.org/10.1103/physreve.101.052205

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