Tabletop laser gives bright soft X-rays

17 Jun 2002

Engineers at Colorado State University in the US have developed a tabletop top device that is one of the brightest sources of millijoule level soft X-ray laser pulses.

The device generates 16.9 nanometre laser pulses with energies of up to one millijoule at a repetition rate of 4Hz. Synchrotron sources of soft X-rays can also yield high average powers but need very rapid pulsing (for example, 500 million pulses per second) so the energy of each pulse is only of the order of nanojoules.

The brightness of the soft X-rays is estimated to be 10²³ photons/(s mm² mrad² 0.01% bandwidth).

The soft X-ray laser pulses were produced by single-pass amplification in a 34.5 centimetre neon-like argon discharge plasma. The researchers say that the X-rays are bright because the plasma column is long.

This device was reported, by C.D. Macchiato, B.R. Benware and J.J. Rocca, in the 15 August 1999 issue of Optics Letters.

SH