English

Josephson Field-Effect Transistors Based on All-Metallic Al/Cu/Al Proximity Nanojunctions

Mesoscale and Nanoscale Physics 2019-08-30 v2 Superconductivity

Abstract

We demonstrate the first \textit{all-metallic} mesoscopic superconductor-normal metal-superconductor (SNS) field-effect controlled Josephson transistors (SNS-FETs) and show their full characterization from the critical temperature TcT_c down to 50 mK in the presence of both electric and magnetic field. The ability of a static electric field -applied by mean of a lateral gate electrode- to suppress the critical current IsI_s in a proximity-induced superconductor is proven for both positive and negative gate voltage values. IsI_s suppression reached typically about one third of its initial value, saturating at high gate voltages. The transconductance of our SNS-FETs obtains values as high as 100 nA/V at 100 mK. On the fundamental physics side, our results suggest that the mechanism at the basis of the observed phenomenon is quite general and does not rely on the existence of a true pairing potential, but rather the presence of superconducting correlations is enough for the effect to occur. On the technological side, our findings widen the family of materials available for the implementation of all-metallic field-effect transistors to \textit{synthetic} proximity-induced superconductors.

Keywords

Cite

@article{arxiv.1903.03435,
  title  = {Josephson Field-Effect Transistors Based on All-Metallic Al/Cu/Al Proximity Nanojunctions},
  author = {Giorgio De Simoni and Federico Paolucci and Claudio Puglia and Francesco Giazotto},
  journal= {arXiv preprint arXiv:1903.03435},
  year   = {2019}
}

Comments

11 pages, 5 color figures