caa a22 4500 445368314 CHVBK 20180317142938.0 cr unu---uuuuu 170323e20110601xx s 000 0 eng 10.1007/s00340-011-4434-2 doi (NATIONALLICENCE)springer-10.1007/s00340-011-4434-2 Enhanced soft X-ray emission from carbon nanofibers irradiated with ultra-short laser pulses [Elektronische Daten] [U. Chakravarty, P. Naik, B. Rao, V. Arora, H. Singhal, G. Bhalerao, A. Sinha, P. Tiwari, P. Gupta] A comparative experimental study of the X-ray emission in the water-window spectral region has been performed using carbon nanofibers (CNFs) of different sizes and graphite plate targets, irradiated with ultra-short (Ti:sapphire) laser pulses. More than an order of magnitude enhancement in the X-ray yield is observed from CNFs of 60-nm diameter with respect to graphite targets. The X-ray emission from CNFs of 160-nm diameter was also high. The integrated X-ray yield of these carbon-based targets scales with the laser intensity (I L) as $I_{\mathrm{L}}^{\sim 1.3-1.4}$ in the intensity range of 4×1016-4×1017W/cm2. The effect of the laser pulse duration on the X-ray emission from the CNFs was also studied by varying the pulse duration from 45 fs up to 3 ps at a constant fluence of 2×104J/cm2. The optimum laser pulse duration for maximum X-ray emission increases with the diameter of the CNFs used. The results are explained from physical considerations of heating and hydrodynamic expansion of the CNF plasma in which resonance field enhancement takes place while passing through two times the critical density. The results add to the efforts towards achieving an efficient low-cost water-window X-ray source for microscopy. Springer-Verlag, 2011 Chakravarty U. Raja Ramanna Centre for Advanced Technology, 452 013, Indore, India aut Naik P. Raja Ramanna Centre for Advanced Technology, 452 013, Indore, India aut Rao B. Raja Ramanna Centre for Advanced Technology, 452 013, Indore, India aut Arora V. Raja Ramanna Centre for Advanced Technology, 452 013, Indore, India aut Singhal H. Raja Ramanna Centre for Advanced Technology, 452 013, Indore, India aut Bhalerao G. Raja Ramanna Centre for Advanced Technology, 452 013, Indore, India aut Sinha A. Raja Ramanna Centre for Advanced Technology, 452 013, Indore, India aut Tiwari P. Raja Ramanna Centre for Advanced Technology, 452 013, Indore, India aut Gupta P. Raja Ramanna Centre for Advanced Technology, 452 013, Indore, India aut Applied Physics B Springer-Verlag 103/3(2011-06-01), 571-577 0946-2171 103:3<571 2011 103 340 https://doi.org/10.1007/s00340-011-4434-2 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00340-011-4434-2 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Chakravarty U. Raja Ramanna Centre for Advanced Technology, 452 013, Indore, India aut NATIONALLICENCE 700 1- Naik P. Raja Ramanna Centre for Advanced Technology, 452 013, Indore, India aut NATIONALLICENCE 700 1- Rao B. Raja Ramanna Centre for Advanced Technology, 452 013, Indore, India aut NATIONALLICENCE 700 1- Arora V. Raja Ramanna Centre for Advanced Technology, 452 013, Indore, India aut NATIONALLICENCE 700 1- Singhal H. Raja Ramanna Centre for Advanced Technology, 452 013, Indore, India aut NATIONALLICENCE 700 1- Bhalerao G. Raja Ramanna Centre for Advanced Technology, 452 013, Indore, India aut NATIONALLICENCE 700 1- Sinha A. Raja Ramanna Centre for Advanced Technology, 452 013, Indore, India aut NATIONALLICENCE 700 1- Tiwari P. Raja Ramanna Centre for Advanced Technology, 452 013, Indore, India aut NATIONALLICENCE 700 1- Gupta P. Raja Ramanna Centre for Advanced Technology, 452 013, Indore, India aut NATIONALLICENCE 773 0- Applied Physics B Springer-Verlag 103/3(2011-06-01), 571-577 0946-2171 103:3<571 2011 103 340 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer