2018/07/05 by Yu. Krupko, V. D. Nguyen, T. Weißl +8 · 2 citations
Physics and Astronomy · #cond-mat.supr-con #cond-mat.mes-hall #quant-ph
paper · pdf · doi:10.1103/physrevb.98.094516
published as Phys. Rev. B 98, 094516 (2018)
arxiv created 2018/07/05 · arxiv updated 2018/09/26
We present a detailed experimental and theoretical analysis of the dispersion and non-linear Kerr frequency shifts of plasma modes in a one-dimensional Josephson junction chain containing 500 SQUIDs in the regime of weak nonlinearity. The measured low-power dispersion curve agrees perfectly with the theoretical model if we take into account the Kerr renormalisation of the bare frequencies and the long-range nature of the island charge screening by a remote ground plane. We measured the self- and cross-Kerr shifts for the frequencies of the eight lowest modes in the chain. We compare the measured Kerr coefficients with theory and find good agreement.