Laser-induced plasmas have emerged as potential sources of soft x-rays and extreme-UV light for applications in spectroscopy, microscopy and lithography. Now researchers at Max Born Institute for Nonlinear Optics and Spectroscopy in Berlin and at the University of Applied Sciences in Remagen, Germany, have produced 11- to 15-nm light that demonstrates a conversion efficiency of up to 0.12 percent by irradiating water jets.The researchers employed the institute's 1047-nm Nd:YLF burst-mode laser, which produces 800-µs bunches of 100 to 800 pulses. By varying the laser energy at pulse durations of 0.03, 0.3 and 3 ns, they created on-target intensities of 1011 to 1015 W/cm2. They reported the work in the Oct. 8 issue of Applied Physics Letters.