Nat. Commun. 8, 15970 (2017)

Wouldn't it be handy to have your very own miniaturized Solar System in the lab, offering the chance to experiment with astronomical events with relative ease? In reality, this is less impossible than it sounds: phenomena that are scale invariant could, in principle, be reproduced in much smaller systems. Now, Gourab Chatterjee and colleagues show that magnetic turbulence is one of them.

Following interaction with ion free-energy sources, the solar wind exhibits different regimes of turbulent behaviour, which are reflected in its magnetic-field spectra. The experiment by Chatterjee and co-workers takes place on a tabletop, and yet presents exactly the same features. The researchers focused a 20-terawatt laser on a millimetre-thick target, generating a plasma with turbulent megagauss magnetic fields. At first these fields are generated by the hot electron currents created by the laser–matter interaction. After 12 picoseconds, a kink appears in the magnetic-energy spectra, which signals the transition to a turbulent regime dominated by the magnetization of the ions — precisely the regime that was found by spacecraft measurements of the solar wind.