We utilize our knowledge of the quantum cloning to attack quantum cryptographic communications. The principle of quantum cryptography is robust, the eavesdropper is always revealed. But in real conditions, using lossy components some amount for transmission errors is tolerated. That is the way for eavesdropper to gain some information without being detected. Our research has clarified the limits for error rate for two well known protocols proposed by Bennett and Brassard...
This work deals with characterization of focused laser beams for the purposes of laser-matter interaction research. Detailed knowledge of transverse energy distribution within the beam profile turns out to be essential for interpretation of the quite nontrivial experimental results. Non-Gaussian beams, which are typical of X-ray lasers, require a rigorous study as well as the interactions they do induce.
We present an extended theoretical background of so-...
We studied experimentally and theoretically the structural transition of diamond under an irradiation with an intense femtosecond extreme ultraviolet laser (XUV) pulse of 24–275 eV photon energy provided by free-electron lasers. Experimental results obtained showed that the irradiated diamond undergoes a solid-to-solid phase transition to graphite, and not to an amorphous state. Our theoretical findings suggest that the nature of this transition is nonthermal, stimulated...
The research showed the feasibility of achieving light amplification up to very high intensities using controlled Brillouin amplification in a plasma. Plasma media, by exciting Raman (electron) or Brillouin (ion) waves, have been used to transfer energy from moderately long, high-energy light pulses to short ones. Using multidimensional kinetic simulations, we defined the optimum window in which a Brillouin scheme can be exploited for amplification and...
The interaction of laser pulses with thin grating targets, having a periodic groove at the irradiated surface, was experimentally investigated. Ultrahigh contrast (∼1012) pulses allowed us to demonstrate an enhanced laser-target coupling for the first time in the relativistic regime of ultrahigh intensity >1019 W/cm2. A maximum increase by a factor of 2.5 of the cutoff energy of protons produced by target normal sheath...
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