Manifestation of anharmonic resonance in the interaction of intense ultrashort laser pulses with microstructured targets

Research output: Contribution to journalArticle

Abstract

Identification of the basic processes responsible for an efficient heating of intense laser produced plasmas is one of the important features of high intensity laser matter interaction studies. Collisionless absorption due to the anharmonicity in the self-consistent electrostatic potential of the plasma, known as anharmonic resonance (AHR), has been proposed to be a basic mechanism but a clear experimental demonstration is needed. Here, we show that microstructured targets enhance X-ray emission and the polarization dependence ascribes the enhancement to anharmonic resonance heating. It is found that p-polarized pulses of 5×1017 W/cm2 intensity bring in a 16-fold enhancement in the X-ray emission in the energy range 20-350 keV compared to s-polarized pulses with microstructured targets. This ratio is 2 for the case of polished targets under otherwise identical conditions. Particle-in-cell simulations clearly show that AHR is the key absorption mechanism responsible for this effect.

Details

Authors
  • Malay Dalui
  • M. Kundu
  • T. Madhu Trivikram
  • Krishanu Ray
  • M. Krishnamurthy
Organisations
External organisations
  • Tata Institute of Fundamental Research
  • TIFR Centre for Interdisciplinary Sciences
  • Institute for Plasma Research
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Fusion, Plasma and Space Physics
Original languageEnglish
Article number103101
JournalPhysics of Plasmas
Volume23
Issue number10
Publication statusPublished - 2016 Oct 1
Publication categoryResearch
Peer-reviewedYes