Laser-driven platform for generation and characterization of strong quasi-static magnetic fields

J. J. Santos; M. Bailly-Grandvaux; L. Giuffrida; P. Forestier-Colleoni; S. Fujioka; Z. Zhang; Ph. Korneev; R. Bouillaud; S. Dorard; D. Batani; M. Chevrot; J. Cross; R. Crowston; J. -L. Dubois; J. Gazave; G. Gregori; E. d'Humières; S. Hulin; K. Ishihara; S. Kojima; E. Loyez; J. -R. Marquès; A. Morace; Ph. Nicolaï; O. Peyrusse; A. Poyé; D. Raffestin; J. Ribolzi; M. Roth; G. Schaumann; F. Serres; V. T. Tikhonchuk; Ph. Vacar; N. Woolsey

arXiv · 1503.00247

Laser-driven platform for generation and characterization of strong quasi-static magnetic fields

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Abstract

Quasi-static magnetic-fields up to $800\,$T are generated in the interaction of intense laser pulses ($500\,$J, $1\,$ns, $10^{17}\,$W/cm$^2$) with capacitor-coil targets of different materials. The reproducible magnetic-field peak and rise-time, consistent with the laser pulse duration, were accurately inferred from measurements with GHz-bandwidth inductor pickup coils (B-dot probes). Results from Faraday rotation of polarized optical laser light and deflectometry of energetic proton beams are consistent with the B-dot probe measurements at the early stages of the target charging, up to $t\approx 0.35\,$ns, and then are disturbed by radiation and plasma effects. The field has a dipole-like distribution over a characteristic volume of $1\,$mm$^3$, which is coherent with theoretical expectations. These results demonstrate a very efficient conversion of the laser energy into magnetic fields, thus establishing a robust laser-driven platform for reproducible, well characterized, generation of quasi-static magnetic fields at the kT-level, as well as for magnetization and accurate probing of high-energy-density samples driven by secondary powerful laser or particle beams.

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J. J. Santos, M. Bailly-Grandvaux, L. Giuffrida, P. Forestier-Colleoni, S. Fujioka, Z. Zhang, Ph. Korneev, R. Bouillaud, S. Dorard, D. Batani, M. Chevrot, J. Cross, R. Crowston, J. -L. Dubois, J. Gazave, G. Gregori, E. d'Humières, S. Hulin, K. Ishihara, S. Kojima, E. Loyez, J. -R. Marquès, A. Morace, Ph. Nicolaï, O. Peyrusse, A. Poyé, D. Raffestin, J. Ribolzi, M. Roth, G. Schaumann, F. Serres, V. T. Tikhonchuk, Ph. Vacar, N. Woolsey. 2015-03-01. Laser-driven platform for generation and characterization of strong quasi-static magnetic fields. https://arxiv.org/abs/1503.00247

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