文章基本信息

标题：Critical current fluctuations in graphene Josephson junctions
本地全文：下载
作者：Mohammad T. Haque ; Marco Will ; Matti Tomi 等
期刊名称：Scientific Reports
电子版ISSN：2045-2322
出版年度：2021
卷号：11
DOI：10.1038/s41598-021-99398-3
语种：English
出版社：Springer Nature
摘要：We have studied 1/f noise in critical current Ic in h-BN encapsulated monolayer graphene contacted by NbTiN electrodes. The sample is close to diffusive limit and the switching supercurrent with hysteresis at Dirac point amounts to ≃5 nA. The low frequency noise in the superconducting state is measured by tracking the variation in magnitude and phase of a reflection carrier signal vrf at 600–650 MHz. We find 1/f critical current fluctuations on the order of δIc/Ic≃10-3 per unit band at 1 Hz. The noise power spectrum of critical current fluctuations SIc measured near the Dirac point at large, sub-critical rf-carrier amplitudes obeys the law SIc/Ic2=a/fβ where a≃4×10-6 and β≃1 at f>0.1 Hz. Our results point towards significant fluctuations in Ic originating from variation of the proximity induced gap in the graphene junction.