Low-Noise Current Amplifier Based on Mesoscopic Josephson Junction

• DOI: 10.1126/science.299.5609.1045
• Publication Date: 2003-02-13T22:06:30Z
• Authors: J. Delahaye; J. Hassel; R. Lindell; M. Sillanpää; M. Paalanen; H. Seppä; P. Hakonen
• Keywords: Coulomb blockade; Mesoscopic physics; Supercurrent; Cooper pair

We used the band structure of a mesoscopic Josephson junction to construct low-noise amplifiers. By taking advantage quantum dynamics junction, i.e., interplay interlevel transitions and Coulomb blockade Cooper pairs, we created transistor-like devices, Bloch oscillating transistors, with considerable current gain high-input impedance. In these correlated supercurrent pairs is controlled by small base made up single electrons. Our devices reached power gains on order 30 5, respectively. The noise temperature was estimated be around 1 kelvin, but temperatures less than 0.1 kelvin can realistically achieved. These provide quantum-electronic building blocks that will useful at low in circuit applications an intermediate impedance level.