Both the stretcher and compressor normally consist of four diffraction gratings. The reflection angle depends on the wavelength and the spacing between the very fine lines inscribed in the grating’s metallic substrate (typical spacing is approximately 1 micrometer). In the final stage of the CPA laser, the pulse is compressed in time by a set of diffraction gratings, in which the shorter wavelengths “catch up” with the longer wavelengths to achieve a cohesive, short-duration, very-high-intensity laser pulse that is focused on a target.Ī diffraction grating is an optical component that separates incoming light into its constituent wavelengths. After this step, shorter (blue) wavelengths of higher frequencies lag behind the longer (red) wavelengths of lower frequencies of the light pulse.
Length scales range from the wavelength and line spacing of about 1 micrometer to the laser beam diameter (d) of about 0.1 meter.ĬPA laser systems first stretch out in time a short pulse of low-intensity light, converting it into a lower-intensity, longer-duration (thousands of times longer) pulse that can be amplified without damaging costly laser optics.
The large range of length scales makes chirped pulse amplification simulations computationally challenging.
