Effect of a second-harmonic current–phase relation on the behavior of a Josephson traveling-wave parametric amplifier

C Claudio Guarcello (Dipartimento di Fisica “E.R. Caianiello,” Università di Salerno 1 , Via Giovanni Paolo II, 132, I-84084 Fisciano (SA),) C Carlo Barone G Giovanni Carapella (Dipartimento di Fisica “E.R. Caianiello,” Università di Salerno 1 , Via Giovanni Paolo II, 132, I-84084 Fisciano (SA),) G Giovanni Filatrella (Science and Technology Department, University of Sannio 3 , Benevento,) A Andrea Giachero (Department of Physics, University of Milano Bicocca 4 , Piazza della Scienza, I-20126 Milano,) S Sergio Pagano

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.

Article Details

Volume / Issue Vol. 126, Issue 16
Published April 21, 2025
ISSN 0003-6951
Publisher American Institute of Physics

Journal Info

Applied Physics Letters

American Institute of Physics

ISSN: 0003-6951 Physical Sciences

Authors (6)

C

Claudio Guarcello

Dipartimento di Fisica “E.R. Caianiello,” Università di Salerno 1 , Via Giovanni Paolo II, 132, I-84084 Fisciano (SA),

C

Carlo Barone

G

Giovanni Carapella

Dipartimento di Fisica “E.R. Caianiello,” Università di Salerno 1 , Via Giovanni Paolo II, 132, I-84084 Fisciano (SA),

G

Giovanni Filatrella

Science and Technology Department, University of Sannio 3 , Benevento,

A

Andrea Giachero

Department of Physics, University of Milano Bicocca 4 , Piazza della Scienza, I-20126 Milano,

S

Sergio Pagano