Enhanced laser-driven ion acceleration by superponderomotive electrons generated from near-critical-density plasma

J. H. Bin; M. Yeung; Z. Gong; H. Y. Wang; C. Kreuzer; M. L. Zhou; M. J. V. Streeter; P. S. Foster; S. Cousens; B. Dromey; J. Meyer-ter-Vehn; M. Zepf; J. Schreiber

doi:10.1103/physrevlett.120.074801

arXiv · 1710.09855

Enhanced laser-driven ion acceleration by superponderomotive electrons generated from near-critical-density plasma

J. H. Bin·M. Yeung·Z. Gong·H. Y. Wang·C. Kreuzer·M. L. Zhou·M. J. V. Streeter·P. S. Foster·S. Cousens·B. Dromey·J. Meyer-ter-Vehn·M. Zepf·J. Schreiber

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Abstract

We report on the experimental studies of laser driven ion acceleration from double-layer target where a near-critical density target with a few-micron thickness is coated in front of a nanometer thin diamond-like carbon foil. A significant enhancement of proton maximum energies from 12 to ~30 MeV is observed when relativistic laser pulse impinge on the double-layer target under linear polarization. We attributed the enhanced acceleration to superponderomotive electrons that were simultaneously measured in the experiments with energies far beyond the free-electron ponderomotive limit. Our interpretation is supported by two-dimensional simulation results.

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J. H. Bin, M. Yeung, Z. Gong, H. Y. Wang, C. Kreuzer, M. L. Zhou, M. J. V. Streeter, P. S. Foster, S. Cousens, B. Dromey, J. Meyer-ter-Vehn, M. Zepf, J. Schreiber. 2017-10-26. Enhanced laser-driven ion acceleration by superponderomotive electrons generated from near-critical-density plasma. https://doi.org/10.1103/physrevlett.120.074801

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