Publications by authors named "Vladimir N Antonov"

Synchronization of Bloch oscillations in small Josephson junctions (JJs) under microwave radiation, which leads to current quantization, has been proposed as an effect that is dual to the appearance of Shapiro steps. This current quantization was recently demonstrated in superconducting nanowires in a compact high-impedance environment. Direct observation of current quantization in JJs would confirm the synchronization of Bloch oscillations with microwaves and help with the realisation of the metrological current standard.

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The a.c. Josephson effect predicted in 1962 and observed experimentally in 1963 as quantized 'voltage steps' (the Shapiro steps) from photon-assisted tunnelling of Cooper pairs is among the most fundamental phenomena of quantum mechanics and is vital for metrological quantum voltage standards.

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Vaccination against Streptococcus pneumoniae is among the most effective measures for preventing pneumonia and reducing the rate of chronic obstructive pulmonary disease (COPD) exacerbations. The objective of this work was to evaluate the long-term effectiveness of PCV13 and PPV23 for preventing pneumonia and COPD exacerbations. The open-label, prospective, observational cohort study involved 302 male patients aged ≥ 45 years: PCV13 group (n = 123); PPV23 group (n = 32); and vaccine-naïve group (n = 147).

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We study operation of a new device, the superconducting differential double contour interferometer (DDCI), in the application for the ultrasensitive detection of magnetic flux and for digital read out of the state of the superconducting flux qubit. DDCI consists of two superconducting contours weakly coupled by Josephson junctions. In such a device a change of the critical current, caused by an external magnetic flux or a nearby electric current, happens in a step-like manner when the angular momentum quantum number changes by one in one of the two contours.

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