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Title: Hot Electron Generation and Manipulation on 'structured' Surfaces

Abstract

We examine ways of generating hotter electrons by coupling more light into structured surfaces (nanoparticle coated surfaces and sub-lambda gratings). It is known that such surfaces produce enhanced x-ray yields. We study the effect of laser prepulse conditions on the enhancement of hard x-ray emission (20 - 200 keV) from plasmas produced on nanoparticle (NP)-coated optically polished copper surface, under different prepulse conditions and observe that enhancement reduces with increasing prepulse intensity. The dynamics of the process is seen to be in the ps regime. We attribute this to preplasma formation on nanoparticles and subsequent modification/destruction of the nanostructure layer before the arrival of the main pulse. We suggest that high-contrast ultrashort pulses are essential for nanoparticles to function as yield enhancers. We exploit surface plasmon coupling of light into sub-lambda grating to switch 'ON' a hotter component in hard x-ray spectra from plasma.

Authors:
; ; ; ; ; ;  [1]
  1. Tata Institute of Fundamental Research, 1, Homi Bhabha Road, Colaba, Mumbai - 400005 (India)
Publication Date:
OSTI Identifier:
20798497
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 827; Journal Issue: 1; Conference: 3. international conference on superstrong fields in plasmas, Varenna (Italy), 19-24 Sep 2005; Other Information: DOI: 10.1063/1.2195244; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; COPPER; COUPLING; ELECTRONS; HARD X RADIATION; KEV RANGE; LASER RADIATION; LASERS; NANOSTRUCTURES; PLASMA; PLASMA HEATING; PLASMA PRODUCTION; PULSES

Citation Formats

Rajeev, P. P., Kahaly, S., Bagchi, S., Bose, S., Kiran, P. P., Ayyub, P., and Kumar, G. Ravindra. Hot Electron Generation and Manipulation on 'structured' Surfaces. United States: N. p., 2006. Web. doi:10.1063/1.2195244.
Rajeev, P. P., Kahaly, S., Bagchi, S., Bose, S., Kiran, P. P., Ayyub, P., & Kumar, G. Ravindra. Hot Electron Generation and Manipulation on 'structured' Surfaces. United States. doi:10.1063/1.2195244.
Rajeev, P. P., Kahaly, S., Bagchi, S., Bose, S., Kiran, P. P., Ayyub, P., and Kumar, G. Ravindra. Fri . "Hot Electron Generation and Manipulation on 'structured' Surfaces". United States. doi:10.1063/1.2195244.
@article{osti_20798497,
title = {Hot Electron Generation and Manipulation on 'structured' Surfaces},
author = {Rajeev, P. P. and Kahaly, S. and Bagchi, S. and Bose, S. and Kiran, P. P. and Ayyub, P. and Kumar, G. Ravindra},
abstractNote = {We examine ways of generating hotter electrons by coupling more light into structured surfaces (nanoparticle coated surfaces and sub-lambda gratings). It is known that such surfaces produce enhanced x-ray yields. We study the effect of laser prepulse conditions on the enhancement of hard x-ray emission (20 - 200 keV) from plasmas produced on nanoparticle (NP)-coated optically polished copper surface, under different prepulse conditions and observe that enhancement reduces with increasing prepulse intensity. The dynamics of the process is seen to be in the ps regime. We attribute this to preplasma formation on nanoparticles and subsequent modification/destruction of the nanostructure layer before the arrival of the main pulse. We suggest that high-contrast ultrashort pulses are essential for nanoparticles to function as yield enhancers. We exploit surface plasmon coupling of light into sub-lambda grating to switch 'ON' a hotter component in hard x-ray spectra from plasma.},
doi = {10.1063/1.2195244},
journal = {AIP Conference Proceedings},
number = 1,
volume = 827,
place = {United States},
year = {Fri Apr 07 00:00:00 EDT 2006},
month = {Fri Apr 07 00:00:00 EDT 2006}
}
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