Hybrid density functional theory calculations for the electronic and optical properties of Fe³⁺-doped KDP crystals

Abstract

The Fe3+ ion is the most common impurity ions in potassium dihydrogen phosphate (KDP) and it can combine with hydrogen vacancies to form cluster defects which may lead to optical...

Study on the optical properties and electronic structures of Ba-doped KH2PO4 crystals

“…20 The kinetic energy cutoff of 680 eV (ref. 6, 11, 13, 14 and 20) is used. The Monkhorst–Pack k -point meshes of 4 × 4 × 2 and 5 × 3 × 3 were used for the calculations of the P-KDP and the F-KDP crystal, respectively.…”

“…21,22 Fe substitution defects were also investigated and two defect states were found to exist in the band gap, they are at 2.2 eV and 6.6 eV and have a 278 nm optical absorption. 11 Zn substitution defects in the KDP crystals were found to lead to large lattice distortions in the H–O bonds affecting the laser-induced damage threshold. 13 However, all these studies are not sufficient to investigate optical properties.…”

“…7 Many investigations considered point defects within the crystal as one of the important influencing factors for the laser-induced damage threshold to be lower than the theoretical value. 1,6,7,[11][12][13][14][15][16] Also, many macroscopic defects are related to high concentrations of point defects, such as inclusions, wedge and craze, which reduce transparency, increase light absorption, and reduce mechanical properties. 10,17 Therefore, it is significant to research the influence of point defects on KDP crystals to enhance device quality and performance.…”

Influence of Ca-substituted K-induced cluster defects on the electronic structure and optical properties of KDP crystals

“…The distortion between K-Ca is much more pronounced than the P-O bond length distortion in PE-KDP. Therefore, the decreased stability of the PE-KDP crystal structure can be considered to be caused by the K-Ca distance distortion in the defective crystals 45 .…”

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

“…It was reported that the influence of impurity cations on the crystal was larger than that of point defects. 8,9 Besides local microscopic stress, it was easy to cause light absorption. Therefore, the LIDT of the KDP crystal was reduced.…”