Influences of Fe3+ ions on rapid growth and laser-induced nonlinear refraction of potassium dihydrogen phosphate crystal

Research on the Nonlinear Absorption Coefficient of 98% Deuterated DKDP Crystal at Fourth-Harmonic-Generation Wavelength

“…For the prismatic samples, whether in z-cut or FHG cut, there was a drop in transmittance in the range of 200-350 nm, indicating that there was a strong linear absorption at 266 nm. It is believed to be caused by the presence of trivalent metal impurity ions, that is, Fe 3+ and Al 3+ , and the intrinsic defects, that is, hydrogen vacancy, interstitial oxygen, and Frenkel pair [29]. It should be noted that the ultraviolet region transmittance of the 3.3 pD value sample was much lower than that of other pD value samples.…”

Study on the defects of KDP crystal with different states by the positron spectroscopy method

“…It could lead to a reduction in the quality of KDP crystals, which was reported by many researchers. 13,14 However, an appropriate concentration of Fe 3+ could increase the metastable zone width. 15,16 Thus, different concentrations of Fe 3+ entering the crystal might not only form replacement impurity defects and could lead to changes in types or distributions for defects.…”

“…Due to the higher growth rate, impurity ions such as Fe 3+ ions were easily adsorbed on the (100) faces. 13,21 Therefore, the difference in defects between the PY and PR sectors should also be paid attention to. Furthermore, thermal annealing is an effective method for improving optical and laser-induced damage properties.…”

Electron paramagnetic resonance spectroscopy and first-principles calculations of Cr3+ doped KDP crystals

“…[3][4][5] However, the behaviour of the impurity ions, once they have entered the crystal, is not yet completely clarified, even for divalent (e.g., Cu 2+ , Co 2+ , Ba 2+ , Fe 2+ ) and trivalent metal ions (e.g., Fe 3+ , Cr 3+ , Al 3+ ), which are currently considered to have the most significant influence. [6][7][8][9] The structure of the KDP crystals at room temperature belongs to the tetragonal crystal system, and the space group is I4 ¯2d. The cell parameters are a = b = 0.7453 nm and c = 0.6974 nm.…”

“…, Fe 3+ , Cr 3+ , Al 3+ ), which are currently considered to have the most significant influence. 6–9…”