Abstract

We have improved a highly coherent x-ray laser at $13.9\mathrm{nm}$ using an oscillator–amplifier configuration. To improve a high-brilliance x-ray laser, we adopted traveling wave pumping for the amplifier target and rotated the amplifier target $3–4\mathrm{mrad}$ in the counterclockwise direction. Thereby, a seed x-ray laser can be amplified by medium plasma of the amplifier target with a high gain coefficient. The amplified x-ray laser has the output energy of $\sim 1.3\mathrm{\mu J}$, corresponding to a large photon flux of $6.5\times {10}^{10}\text{\hspace{0.17em} photons}/\text{pulse}$ and a high peak brilliance of $5\times {10}^{26}\text{\hspace{0.17em}photons}/(\mathrm{s}\cdot {\mathrm{mm}}^2\cdot {\mathrm{mrad}}^2\cdot 0.01\%\text{\hspace{0.17em} bandwidth})$.

© 2008 Optical Society of America