Efficient fusion neutron generation from heteronuclear clusters in intense femtosecond laser fields

H. Y. Lu, J. S. Liu, C. Wang, W. T. Wang, Z. L. Zhou, A. H. Deng, C. Q. Xia, Y. Xu, X. M. Lu, Y. H. Jiang, Y. X. Leng, X. Y. Liang, G. Q. Ni, R. X. Li, and Z. Z. Xu

Accepted Thursday Nov 05, 2009

We demonstrate experimentally the efficient fusion neutron generation from Coulomb explosion (CE) of laser irradiated large-size heteronuclear deuterated methane clusters. A conversion efficiency of 2.1×106 neutrons per joule of incident laser energy is obtained with a 120-mJ, 70-fs laser pulse. It is 50 times higher than that of homonuclear deuterium clusters of similar size. This enhancement is attributed to the significant increase in the deuteron kinetic energies by 4 folds due to energetic boosting and overrun effects during CE of heteronuclear clusters. The yield of 5.5×106 neutrons per pulse is obtained with a 100-TW 50-fs driving laser pulse at an intensity of 1.5×1019W/cm2. This work may facilitate the development of a high-flux table-top neutron source.