Infrared absorption of fs-laser textured CVD diamond

Nanoscale periodic texturing on polycrystalline CVD diamond surface was performed to obtain a significant increase in optical absorptance to visible and nearinfrared radiation. Surface texturing, obtained by the use of fs-laser ultrashort pulses, has been demonstrated to induce a controlled periodicity of ripples of about 170 nm and length of several lm, able to drastically increase the diamond capability of interacting with solar radiation from its intrinsic visible blindness. Ultraviolet and visible Raman spectroscopy has been used to confirm the absence of nondiamond phases resulting from the process for the fs-lasertextured sample. Moreover, here we investigate the optical properties in the range 200 nm–25 µm. Absorbance of fs laser-textured CVD diamond is considerably higher than the untreated one at every wavelength, resulting in a remarkable increase in the emittance: It points out the need for an optimization of process parameters to enhance the selective absorption capability.