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Full-Text Articles in Physics
Chaotic Free-Space Laser Communication Over Turbulent Channel, N. F. Rulkov, Mikhail Vorontsov, L. Illing
Chaotic Free-Space Laser Communication Over Turbulent Channel, N. F. Rulkov, Mikhail Vorontsov, L. Illing
Electro-Optics and Photonics Faculty Publications
The dynamics of errors caused by atmospheric turbulence in a self-synchronizing chaos-based communication system that stably transmits information over a ∼5 km free-space laser link is studied experimentally. Binary information is transmitted using a chaotic sequence of short-term pulses as a carrier. The information signal slightly shifts the chaotic time position of each pulse depending on the information bit. We report the results of an experimental analysis of the atmospheric turbulence in the channel and the impact of turbulence on the bit-error-rate performance of this chaos-based communication system.
Cooling Atoms In An Optical Trap By Selective Parametric Excitation, Nicola Poli, Robert J. Brecha, Giacomo Roati, Giovanni Modugno
Cooling Atoms In An Optical Trap By Selective Parametric Excitation, Nicola Poli, Robert J. Brecha, Giacomo Roati, Giovanni Modugno
Physics Faculty Publications
We demonstrate the possibility of energy-selective removal of cold atoms from a tight optical trap by means of parametric excitation of the trap vibrational modes. Taking advantage of the anharmonicity of the trap potential, we either selectively remove the most energetic trapped atoms or excite those at the bottom of the trap by tuning the parametric modulation frequency. This process, which had been previously identified as a possible source of heating, also appears to be a robust way for forcing evaporative cooling in anharmonic traps.