التحقيق في خصائص إنتاج البلازما لموجهات التفريغ الشعرية

This paper investigates the testing of plasma waveguides that are suitable for the guiding of high power
femtosecond laser pulses in non-linear laser-plasma interaction experiments. Plasma is created by ionising the gas
injected into the capillary using a high voltage pulse. Two waveguides were used: each is 4 cm in length but with a
different capillary diameter profile. The first waveguide was a linear (straight) waveguide with a constant diameter
of 288 μm and the second featured a taper in its diameter from 289 – 232 μm. To characterise the performance of
each capillary, high voltage testing was undertaken using a vacuum chamber. The straight capillary produced a
steady current of 320 A with a voltage input of 17kV. The tapered capillary was tested with the current flowing from
the large end to the small end to produce a reasonably stable current of 300 A with an input voltage of 16 kV. In
both straight and tapered capillaries, the temporal fluctuations of the current pulse demonstrates excellent stability of
the plasma current.