Boron-Proton Nuclear-Fusion Enhancement Induced in Boron-Doped Silicon Targets by Low-Contrast Pulsed Laser

Transcription

1 Boron-Proton Nuclear-Fusion Enhancement Induced in Boron-Doped Silicon Targets by Low-Contrast Pulsed Laser Georg Korn, Daniele Margarone, Antonino Picciotto ELI-Beamlines Project Institute of Physics of the Czech Academy of Science PALS Centre Prague, Czech Republic IZEST ELI-NP, September 214, Paris 1

2 Acknowledgements A. Picciotto 1, P. Bellutti 1, M. Crivellari 1, A. Mangione 2 1 Microtechnologies Laboratory, Fondazione Bruno Kessler, Trento, Italy 2 Institute of Advanced Technologies, Trapani, Italy A.Velyhan 3, J. Krasa 3, J. Prokupek 4, E. Krousky 4, J.Ullschmied 4, L. Laska 3, G.Korn 3 3 Institute of Physics of the ASCR, ELI-Beamlines project, Prague, Czech Republic 4 Institute of Plasma Physics of the ASCR, PALS laboratory, Prague, Czech Republic A. Szydlowsky 5, A. Malinowska 5 5 Institute of Plasma Physics and Laser Microfusion, Warsaw, Poland G. Bertuccio 6, Y. Shi 6 6 Politecnico di Milano, Department of Electronics Information and Bioengineering, Como, Italy M. Kucharik 7 7 Czech Technical University in Prague, FNSPE, Czech Republic 2

3 Contents State-of-the-art Proposed scheme (multilayer target + ns shaped pulse) Experimental results (Laserlab Europe PALS) Conclusions and Perspectives 3

4 11 B(p,α)2a 11 B+ p 3α MeV First investigation in the 193s: Oliphant & Rutherford, L. Proc. R. Soc. London A 141 (1933) 259 Dee and Gilbert, L. Proc. R. Soc. London A 154 (1936) 279 Interest for future «ultraclean» nuclear fusion reactors: Rostoker et al, Science 278 (1997) 1419 Kulcinski & Santarius, Nature 396 (1998) 725 Hora et al, Energy Environ. Sci. 3 (21) 479 Numerical & Exp. (standard accelerators) studies: Dmitriev, Physics of Atomic Nuclei 72, 1165 (29) Stave et al, Phys. Lett. B 696 (211) 26 Maximum cross section: 675 kev (p) Main channel: a energy of 2-6 MeV ~4 MeV) Secondary channel: a energy of 6 1 MeV Nevins & Swain, Nuclear Fusion 4 (2) 865 4

5 Laser-driven p-b fusion exp. First experiment Recent exp. result! Belyaev et al, Phys. Rev. E 72 (25) 2646: a yield: ~1 3 /sr/pulse Laser energy: 15 J Laser pulse: 1.5 ps Laser intensity: W cm 2 Target: massive BCH (5% of 11 B) a yield: ~1 7 /sr/pulse Laser 1 energy: 2 J Laser 1 pulse: 1 ps Laser 1 intensity: W cm 2 Target 1: 2 mm Al Laser 2 energy: 4 J Laser 2 pulse: 1.5 ns Laser 2 intensity: W cm 2 Target 2: massive natural B 5

6 I L [a.u.] Our PALS Laserlab Europe project: PALS_177 (January 213) Laser energy: 5 J Laser pulse:.3 ns (FWHM) Laser wavelength: 1315 nm Focal spot diameter: 8 mm -I (-1 ns): 2 mj W cm 2 I-II ( ns): 55 J 1 15 W cm 2 II-III ( ns): 5 J W cm I II III L [ns] E L (ns,1ns) = 1.68 mj E L (1ns,1.85ns) = 56 J E L (1.85ns, 2.15ns) = 488 J 6

7 Target geometry MicroTechnologies Laboratory FBK (Trento): - H-enriched Si: thermal annealing Picciotto et al, Europhys. Lett. 92 (21) 348 Picciotto et al, J. Appl. Phys. Express 4 (211) B-enriched Si: (i) thermal annealing, (ii) 5 kev ionimplantation (doping processes in semiconductors) Laser SiHB diff SiHB impl Si A. Picciotto Target geometries - SiHB diff :.5mm thick, 1 2 cm B (>1 mm) 2/1mm thick - SiHB impl :.5mm thick, 1 22 cm B (@19 nm) - Si:.5mm thick 7

8 Z (μm) Z (μm) Z (μm) Hydrodynamic simulations of pre-pulse 2D PALE (Prague Arbitrary Lagrangian-Eulerian) code R. Liska et al., Finite Volumes for Complex Applications VI: Problems & Perspectives, Springer Proceedings in Mathematics 2 (211) ns 5x SiHB impl ns r(μm) 5x SiHB dep r(μm) SiHB diff ns 5x r(μm).5 8

9 Simplified model ( artistic view ) 9

10 Experimental setup Ion diagnostics TP: Thomson Parabola spectrometer TOF-SiC: silicon carbide detectors Margarone et al. J. Appl. Phys. 19, 1332 (211) Bertuccio et al., Proceedings of SPIE, 7679 PM-355: solid state nuclear track detectors Szydłowski et al., Radiat. Meas. 34 (21) 325 Malinowska et al, Nucl. Instr. and Meth. (21) 1

11 Track diameters [mm] track No. [a.u.] track No. [a.u.] Alpha measurements (PM-355) SiHB impl 2 Alpha particles Si-H-B target 1 Si Track diameter [mm] 2 Protons Si target Track diameter [mm] - Detection distance: 5 cm - Detection angles: - 5 (target normal) - Al filters: 6 3 μm (15 μm) Alphas 2h etching time Protons 2h etching time Energy [MeV] 11

12 tracks diameter, mm counts tracks (au) counts tracks (au) SiHB impl SiHB diff Track's diameter, mm Boron implanted target Boron diffused target Track's diameter, mm alfa particles calibration curve for 1h etching time Energy, MeV 12

13 Particle Yield [sr -1 ] Yield [sr -1 ] Alpha energy & angular distribution 3x1 8 Maximum alpha yield: 1 9 /sr/pulse 2x1 8 1x Energy [MeV] Total alpha number: /pulse - 2 x 1 3 times higher than Belyaev et al. (correction suggested in Kimura et al, PRE 79 (29)) with 1.5-ps pulse width and W cm 2 intensity - 1-times higher than Labaune et al. (1 7 /sr/pulse) with two laser beams (ns and ps) and two targets. Long laser pulse (ns-class), low contrast, maximum nominal laser intensity about 1- times lower (3x1 16 W cm -2 ) 1,x1 9 5,x1 8, Angle [degrees] 13

14 Alpha TOF (SiC) measurements f det =65 8mm Al-flter a 1 : (4.6 ±2%) MeV a 2 : (8.9 ±12%) MeV dn/de [(MeV) -1 ] I L =3x1 16 W cm -2 L =.3ns (FWHM) p 1 1 Energy [MeV] alpha (SiC-fit) prot. (TP) a a 14

15 Conclusions and Perspectives Experimental achievements - Intense alpha source (1 9 /sr/pulse) - High directionality (3 ) - Quasi-monoenergetic features (25% energy spread) - Simple irradiation geometry (1 laser pulse and 1 layered target) - Moderate laser requirements (ns-class pulse, moderate laser intensity) Future optimization - Laser pulse temporal shaping (1 ps) and ns contrast improvement - Laser energy (< 1 J???) - Target thickness, B concentration, B depth (using Si microtechnology) - Scaling with lower energy systems (newly developed high rep. rate diode-pumped lasers) - Scaling with higher energy systems (fusion systems) - applications in ion stopping power in plasmas/wdm 15

16 Thank you for your kind attention! 16