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Study of x-ray emission enhancement via high contrast femtosecond laser interacting with solid foil

L. M. Chen·M. Kando·S. V. Bulanov·J. Koga·K. Nakajima·T. Tajima·M. H. Xu·X. H. Yuan·Y. T. Li·Q. L. Dong·J. Zhang
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Abstract

We studied the hard x-ray emission and the K-alpha x-ray conversion efficiency produced by 60 fs high contrast frequency doubled Ti: sapphire laser pulse focused on Cu foil target. Cu K-alpha photon emission obtained with second harmonic laser pulse is more intense than the case of fundamental laser pulse. The Cu K-alpha conversion efficiency shows strong dependence on laser nonlinearly skewed pulse shape and reaches the maximum value 4x10-4 with 100 fs negatively skewed pulse. It shows the electron spectrum shaping contribute to the increase of conversion efficiency. Particle-in-cell simulations demonstrates that the application of high contrast laser pulses will be an effective method to optimize the x-ray emission, via the Enhanced Vacuum Heating mechanism.

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L. M. Chen, M. Kando, S. V. Bulanov, J. Koga, K. Nakajima, T. Tajima, M. H. Xu, X. H. Yuan, Y. T. Li, Q. L. Dong, J. Zhang. 2006-07-11. Study of x-ray emission enhancement via high contrast femtosecond laser interacting with solid foil. https://arxiv.org/abs/physics/0607091

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