Fast electron generation and transport in high-intensity laser–solid interactions induces X-ray emission and drives ion acceleration.Effective production of these sources hinges on an efficient laser absorption into ...Fast electron generation and transport in high-intensity laser–solid interactions induces X-ray emission and drives ion acceleration.Effective production of these sources hinges on an efficient laser absorption into the fast electron population and control of divergence as the beam propagates through the target.Nanowire targets can be employed to increase the laser absorption,but it is not yet clear how the fast electron beam properties are modified.Here we present novel measurements of the emittance of the exiting fast electron beam from irradiated solid planar and nanowire targets via a pepper-pot diagnostic.The measurements indicate a greater fast electron emittance is obtained from nanowire targets.Two-dimensional particle-in-cell simulations support this conclusion,revealing beam defocusing at the wire–substrate boundary,a higher fast electron temperature and transverse oscillatory motion around the wires.展开更多
基金the NextGenerationEU(PNRR)Integrated Infrastructure Initiative in Photonic and Quantum Sciences(IPHOQS)(CUP B53C22001750006,ID D2B8D520,IR0000016)EuPRAXIA Advanced Photon Sources(EuAPS)(CUP I93C21000160006,IR0000030)+3 种基金funding from the Engineering and Physical Sciences Research Council(EP/L01663X/1)the Royal Society International Exchange(IES/R3/170248)Computing resources were provided by STFC Scientific Computing Department’s SCARF clusterfunded by the UK EPSRC(grants EP/G054950/1,EP/G056803/1,EP/G055165/1 and EP/M022463/1).
文摘Fast electron generation and transport in high-intensity laser–solid interactions induces X-ray emission and drives ion acceleration.Effective production of these sources hinges on an efficient laser absorption into the fast electron population and control of divergence as the beam propagates through the target.Nanowire targets can be employed to increase the laser absorption,but it is not yet clear how the fast electron beam properties are modified.Here we present novel measurements of the emittance of the exiting fast electron beam from irradiated solid planar and nanowire targets via a pepper-pot diagnostic.The measurements indicate a greater fast electron emittance is obtained from nanowire targets.Two-dimensional particle-in-cell simulations support this conclusion,revealing beam defocusing at the wire–substrate boundary,a higher fast electron temperature and transverse oscillatory motion around the wires.