EUV stimulated emission from MgO pumped by FEL pulses

Philippe Jonnard (1) , Jean-­‐michel André (1) , Karine Le Guen (1) , Meiyi Wu (1) , Emiliano Principi (2) , Alberto Simoncig (2) , Alessandro Gessini (2) , Riccardo Mincigrucci (2) , Claudio Masciovecchio (1)

1 LCPMR - Laboratoire de Chimie Physique - Matière et Rayonnement
2 Elettra Sincrotrone Trieste

Stimulated emission is a fundamental process in nature that deserves to be investigated and understood in the EUV and X-ray regimes. Today this is definitely possible through high energy density FEL beams. In this context, we show for the first time, evidence for soft-x-ray stimulated emission from a MgO solid target pumped by extreme ultraviolet FEL pulses formed in the regime of travelling-wave amplified spontaneous emission in backward geometry. Our results combine two effects separately reported in previous works: emission in a privileged direction and existence of a material-dependent threshold for the stimulated emission. We have developed a novel theoretical framework, based on coupled rate and transport equations, capable to predict the phenomenology of the stimulated X-ray emission from condensed materials. Our model, accounts for both observed mechanisms that are the privileged direction for the stimulated emission of the Mg L2,3 characteristic emission and the pumping threshold.

Mots clés: Stimulated emission; MgO; FEL

Domaines: Physique Générale [physics.gen-ph]

Philippe Jonnard, Jean-­‐michel André, Karine Le Guen, Meiyi Wu, Emiliano Principi, et al.. EUV stimulated emission from MgO pumped by FEL pulses. 2016. ⟨hal-01344717v1⟩