Coherent emission from disordered arrays of driven Josephson vortices

We propose a mechanism of coherent emission from driven vortices in stacked intrinsic Josephson junctions. In contrast to super-radiance, which occurs only for highly ordered vortex lattices, we predict resonant radiation emission from weakly correlated vortex arrays. Our analytical results for the THz wave intensity, resonance frequencies, and the dependence of THz emission power on dissipation are in good agreement with the ones obtained by recent simulations.Comment: 2 figure

Nonlinear picosecond-pulse propagation through optical fibers with positive group velocity dispersion

The predictions of the nonlinear Schrodinger equation have been tested by passing 5.5-psec optical pulses through a 70-m single-mode optical fiber. With use of a precise cross correlation technique based on pulse compression, dramatic reshaping of the input pulses into flat-topped, frequency-broadened, and positively chirped 20-psec output pulses with self-steepened fall times of less than 2 psec was observed. The observations are in good agreement with theory.Peer reviewedElectrical and Computer Engineerin

Observation of the formation of an optical intensity shock and wave breaking in the nonlinear propagation of pulses in optical fibers

We have observed the formation of an optical intensity shock and the subsequent wave breaking in the nonlinear propagation of 1-psec pulses in an optical fiber. The wave breaking manifests itself as the appearance of oscillations trailing the shock, which are due to the beating of widely separated frequency components which bridge the shock. The experimental results are in good agreement with numerical solutions of the nonlinear Schrodinger equation.Peer reviewedElectrical and Computer Engineerin

NESTOR: A neutrino particle astrophysics underwater laboratory for the Mediterranean

Abstract An underwater neutrino astrophysics laboratory, to be located in the international waters off the Southwest of Greece, near the town of Pylos is now under construction. In the last two years a group of physicists from Greece and Russia have carried out two demonstration experiments in 4km deep water, counting muons and verifying the adequacy of the deep sea site. Plans are presented for a 100, 000 m 2 high energy neutrino detector composed of a hexagon of hexagonal towers, with 1176 optical detector units. A progress report is given and the physics potential of a siggle tower with 168 phototubes (currently under construction) is described

Mass-loss from Io’s volcanic atmosphere: A unique synergy with the Juno Io fly-by

Material outgassed from Io’s volcanic activity forms its tenuous SO2-based atmosphere, and ultimately becomes ionized to populate Jupiter’s magnetosphere. However, the direct link between Io’s volcanoes and the plasma in the jovian system remains unclear; the gas is not vented at sufficient velocities to escape Io, and the atmosphere should therefore act as a buffer, with mass-loss occurring from the upper bulk atmosphere rather than directly from plumes. The mechanics of this process, and the role of the atmosphere, remain elusive in part because every component of this system is highly time-variable so that linking different components observed at different times is nearly impossible. The Juno extended mission’s close Io fly-by provides a truly unique opportunity to measure particles in the vicinity of Io in situ with Juno, while simultaneously mapping the temperature and column density of Io’s dayside atmosphere with JWST. We propose to measure the SO2 gas in Io’s atmosphere during the 1 hour surrounding Juno’s closest approach, via the 7.3 micron gas band observed with MIRI/MRS. This gas band is clearly seen in JWST ERS observations of Io, which targeted Io’s leading hemisphere. Fortuitously, the Juno fly-by takes place downstream of Io, measuring the lost matter, and also while Io’s trailing hemisphere is visible to JWST. This hemispheric coverage complements the viewing geometry of the ERS data, and we will additionally observe Io across 5-6 microns to measure hemispheric differences in 5.4 and 5.95 micron bands that were newly detected in the ERS data of I

NESTOR - A NEUTRINO PARTICLE ASTROPHYSICS UNDERWATER LABORATORY FOR THE MEDITERRANEAN

An underwater neutrino astrophysics laboratory, to be located in the international waters off the Southwest of Greece, near the town of Pylos is now under construction. In the last two years a group of physicists from Greece and Russia have carried out two demonstration experiments in 4km deep water, counting muons and verifying the adequacy of the deep sea site. Plans are presented for a 100,000 m2 high energy neutrino detector composed of a hexagon of hexagonal towers, with 1176 optical detector units. A progress report is given and the physics potential of a single tower with 168 phototubes (currently under construction) is described