<title>The spectrum of up-converted broadband radiation in nonlinear optical crystals</title>

Upconversion of Broadband Infrared Radiation into Visible Light for Different Pumping Parameters

“…where is a constant proportional to the squared component of the nonlinear susceptibility tensor, 1 ( 1 ) and 2 ( 2 ) are the intensities of interacting light waves, is the length of a crystal along the propagation directions of waves, and Δ is the disturbance of phase matching. The disturbance of phase matching is given as [8][9][10][11][12][13]…”

“…where , and are refractive indexes for ordinary and extraordinary waves at the respective frequencies. The intensity of the converted broadband radiation at the crystal output was calculated by taking into account the interactions of noncollinear light beams along all possible directions within the angle range of an input convergent beam of infrared broadband radiation [9][10][11][12]:…”

“…This study investigates the influence of pump radiation parameters such as the polarization and spectral width of infrared radiation on the conversion of broadband infrared radiation in nonlinear optical crystals. The spectra of converted broadband infrared radiation in nonlinear optical crystals were calculated by taking into account the noncollinear interactions of light waves [12]. Approximate calculations were carried out when the power of a generated wave is so small that it is possible to consider the amplitudes of two propagating waves to have been constant through the entire length of a crystal.…”