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13Complex Systems of Charged Particles and their Interactions with Electromagnetic Radiation 2019
COHERENT X-RAY MIRAGE: DISCOVERY, THEORY AND POSSIBLE
APPLICATIONS
S.A. Magnitskiy
Physics Faculty and International Laser Center ofM.V. Lomonosov Moscow State University, Moscow, Russia, e-mail: sergeymagnitskiy@gmail.com
The talk presents the results of studies of the amplification of an X-ray pulse in plasma resulting from the focusing of p[powerful laser pulses on a silver target surface. The work was carried out in collaboration with A.Ya. Faenov's group and resulted in the discovery of the X-ray phantom phenomenon [1].
In contemporary view, X-rays are electromagnetic radiation different from visible light only in wavelength. Still, over more than a century of fruitful studies of X-rays the remarkable phenomenon of optical phantoms [2] had never been observed in the X-ray range due to the fact that the refraction index for it is for most materials close to unity. The situation changed with the creation of laser-driven plasmas which are, in particular, used as active media in table-top transient oscillator-aplifier lasers [3]. An optical phantom in the X-ray range was registered in a two-cascade laser of this type. We found out that the phantom arises in the amplifier in the form of a virtual coherent point source securely synchronized in phase with the generator radiation. A theory of the phenomenon based on the wave optics techniques was developed.
Fig. 1. Overview of the experimental setup at Kansai Photon Science Institute of Japan Atomic Energy Agency which was used to amplify optical pulses in the soft X-ra range
References
[1] Magnitskiy, S., Nagorskiy, N., Faenov, A., Pikuz, T., Tanaka, M., Ishino, M., Nishikino, M., Fukuda, Y., Kando, M., Kawachi, T. and Kato, Y., 2013. Observation and theory of X-ray mirages. Nature communications, 4, p.1936.
[2] Monge, G. A memoir relative to the optical phenomenon, known by the name of mirage ( in Memoirs Relative to Egypt... ,Phillips, London, 1800).
[3] Nishikino, M. et al. Characterization of a high-brillance soft x-ray laser at 13.9 nm by use of an oscillator-amplifier configuration, Applied Optics 47, 1129 - 1134 (2008).
