Computational tools for Josephson traveling wave parametric amplifiers in frequency domain and time domain

We present our latest simulation results on Josephson traveling wave parametric amplifiers (TWPAs) fabricated with our Nb/Al-AlO_x/Nb junction process [1,2,3]. These amplifiers are tailored for the readout of semiconducting and superconducting quantum devices at sub-GHz frequencies and at 4-8 GHz, respectively. We have adopted an open-source, frequency-domain simulation code JosephsonCircuits.jl [4] and tested it with various TWPA circuits. As an example, we have found good agreement with experimental data [2] on our four-wave mixing TWPA. We describe the development of a custom time-domain simulation code programmed in Julia language [5] to complement the harmonic balance method used in [4].



[1] Leif Grönberg et al., Supercond. Sci. Technol. 30, 125016 (2017).

[2] Slawomir Simbierowicz, Visa Vesterinen, et al., Rev. Sci. Instrum. 92, 034708 (2021).

[3] M. R. Perelshtein et al., Phys. Rev. Applied 18, 024063 (2022).

[4] Kaidong Peng et al., “X-parameter based design and simulation of Josephson traveling-wave parametric amplifiers for quantum computing applications”, in 2022 IEEE International Conference on Quantum Computing and Engineering (QCE), pp. 331-340.

[5] Jaani Nissilä et al., Appl. Phys. Lett. 119, 032601 (2021), supplementary material.