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arXiv · 1006.4454

A bright point source of ultrashort hard x-rays from laser bioplasmas

M. Krishnamurthy·Sudipta Mondal·Amit D. Lad·Saima Ahmad·V. Narayanan·R. Rajeev·M. Kundu·G. Ravindra Kumar·Krishanu Ray
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Abstract

Micro and nano structures scatter light and amplify local electric fields very effectively. Energy incident as intense ultrashort laser pulses can be converted to x-rays and hot electrons more efficiently with a substrate that suitably modifies the local fields. Here we demonstrate that coating a plain glass surface with a few micron thick layer of an ubiquitous microbe, {\it Escherichia coli}, catapults the brightness of hard x-ray bremsstrahlung emission (up to 300 keV) by more than two orders of magnitude at an incident laser intensity of 10$^{16}$ W cm$^{-2}$. This increased yield is attributed to the local enhancement of electric fields around individual {\it E. coli} cells and is reproduced by detailed particle-in-cell (PIC) simulations. This combination of laser plasmas and biological targets can lead to turnkey, multi-kilohertz and environmentally safe sources of hard x-rays.

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M. Krishnamurthy, Sudipta Mondal, Amit D. Lad, Saima Ahmad, V. Narayanan, R. Rajeev, M. Kundu, G. Ravindra Kumar, Krishanu Ray. 2010-06-23. A bright point source of ultrashort hard x-rays from laser bioplasmas. https://arxiv.org/abs/1006.4454

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