Multilayer Structures For X-Ray Laser Cavities

Recent demonstrations of the generation of amplified spontaneous emission (ASE) at soft x-ray wavelengths have spurred interest in normal incidence multilayer structures for use as x-ray laser (XRL) cavity mirrors. Calculations indicate that cavity mirrors can provide significant enhancement of XRL output, and drive the oscillations to the saturation limit. Novel ideas for cavity output coupling may expand the versatility of XRL devices, while encouraging the marriage of lithographic and multilayer technologies to the general benefit of x-ray optics. Preliminary tests of a double pass cavity have already been conducted. These tests point out the importance of detailed cavity design issues, such as precision mirror alignment, mirror damage dynamics, and detailed mirror calibration to the future success of this field.