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This paper describes the performance of a new turn-key AC quantum voltmeter, an AC Josephson voltage standard system, used for calibration of common DC and AC voltage standards. The capabilities and handling of the system in an industrial environment were investigated and are discussed here. Several Fluke 5700A series calibrators were tested and their(More)
To verify the fundamental Gerasimov-Drell-Hearn (GDH) sum rule for the first time experimentally, we measured the helicity dependent total photoabsorption cross section with circularly polarized real photons and longitudinally polarized nucleons in the photon energy range 0.68-1.82 GeV with the tagged photon facility at ELSA. The experiment was carried out(More)
A Voltage Calibrator based on a 10-V programmable Josephson Array that is simple to use, provides DC and AC calibration up to kHz range for industry-common equipment, and ensures direct traceability to a quantum-based standard, is under development. This device has proven to excel conventional DC standard systems and will extend into low frequency AC range,(More)
The AC Quantum Voltmeter, which was a breakthrough as an accredited, industrial-tested, fast and easy-to-use DC and AC voltage quantum-based calibrating system, has now been taken one step further with new extensive capabilities covering resistance and current measurements. Using equipment readily available in calibration laboratories, the new Quantum(More)
A second harmonic push-push VCO with auxiliary fundamental frequency output is presented. The fundamental frequency is extracted directly from the base of the transistor using only a small coupling capacitor. By this method a simple means is provided to extend the upper frequency limit of standard PLL stabilization based on ECL dividers (fmax = 1.5 - 1.8(More)
Helicity-dependent total photoabsorption cross sections on the deuteron have been measured for the first time at ELSA (Bonn) in the photon energy range from 815 to 1825 MeV. Circularly polarized tagged photons impinging on a longitudinally polarized LiD target have been used together with a highly efficient 4pi detector system. The data around 1 GeV are not(More)
For the first time we checked the fundamental Gerasimov-Drell-Hearn (GDH) sum rule for the proton experimentally in the photon energy range from 0.2-2.9 GeV with the tagged photon facilities at MAMI (Mainz) and ELSA (Bonn). New data of the doubly polarized total cross section difference are presented in the energy range from 1.6 to 2.9 GeV. The contribution(More)
This paper describes the properties of a 10 V programmable Josephson voltage standard (PJVS) array operated in a cryocooler. The operating margins at 70 GHz frequencies are discussed and compared to liquid helium cooling. A crucial factor is the limited heat conduction between PJVS chip and cold stage. A method is presented to estimate the heat conduction(More)
We investigate the Fano-type line shape of the Ba mode of Y1−xCaxBa2Cu3O6+y films observed in Raman spectra with A1g symmetry. The line shape is described with an extended Fano formula that allows us to obtain the bare phonon parameters and the self-energy effects based on a phenomenological description of the real and imaginary part of the lowenergy(More)
In Raman spectra of cuprate superconductors the gap shows up both directly, via a redistribution of the electronic background, the so-called " 2∆ peaks " , and indirectly, e.g. via the renormalization of phononic excitations. We use a model that allows us to study the redistribution and the related phonon self-energy effects simultaneously. We apply this(More)
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