We numerically investigate the behavior of a Josephson traveling-wave parametric amplifier assuming a current–phase relation with a second-harmonic contribution. We find that varying the weight of harmonic terms in the Josephson current affects the gain profile. The analysis of gain characteristics, phase-space portraits, Poincaré sections, and Fourier spectra demonstrates that the nonsinusoidal contribution influences the operating mode and stability of the device. In particular, we identify the optimal weighting of harmonic contributions that maximizes amplification, achieving gains up to ∼13 dB in a device without dispersion engineering.
Effect of a second-harmonic current–phase relation on the behavior of a Josephson traveling-wave parametric amplifier
Guarcello C.
Writing – Original Draft Preparation
;Barone C.Writing – Review & Editing
;Carapella G.Conceptualization
;Pagano S.Writing – Review & Editing
2025
Abstract
We numerically investigate the behavior of a Josephson traveling-wave parametric amplifier assuming a current–phase relation with a second-harmonic contribution. We find that varying the weight of harmonic terms in the Josephson current affects the gain profile. The analysis of gain characteristics, phase-space portraits, Poincaré sections, and Fourier spectra demonstrates that the nonsinusoidal contribution influences the operating mode and stability of the device. In particular, we identify the optimal weighting of harmonic contributions that maximizes amplification, achieving gains up to ∼13 dB in a device without dispersion engineering.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
