Lead Mixed Oxyhalides Satisfying All Fundamental Requirements for High‐Performance Mid‐Infrared Nonlinear Optical Materials

Abstract

To design high‐performance mid‐infrared (mid‐IR) nonlinear optical (NLO) materials, we have focused on the combination of a heavy metal lone pair cation, Pb2+ and mixed oxyhalides. A systematic investigation in PbO‐PbCl2‐PbBr2 system led us to discover the first examples of NLO lead mixed oxyhalides, namely, Pb13O6Cl4Br10, Pb13O6Cl7Br7, and Pb13O6Cl9Br5. All the reported materials have remarkably comprehensive properties including broad IR transparency (up to 14.0 μm), qualified second harmonic generation (SHG) responses (0.6–0.9×AgGaS2), wide band gaps (3.05–3.21 eV), and ease of crystal growth. Interestingly, a centimeter‐sized single crystal (2.9×1.3×0.5 cm3) of Pb13O6Cl9Br5 revealing a wide transparent range (0.384–14.0 μm) and high laser damage threshold (LDT) (14.6×AgGaS2) has been successfully grown in an open system. The study suggests that all the reported mixed oxyhalides are outstanding candidates for mid‐IR NLO materials.

Two new tellurite halides with cationic layers: syntheses, structures, and characterizations of CdPb2Te3O8Cl2 and Cd13Pb8Te14O42Cl14

“…As shown in Fig. 3c and d, the experimental band gaps are determined to be 3.89 eV for CdPb 2 Te 3 O 8 Cl 2 and 3.78 eV for Cd 13 Pb 8 Te 14 O 42 Cl 14 , which are comparable to the ones in previously reported tellurite compounds like α-CdTeO 3 (3.91 eV) 46 and larger than the ones in Pb 17 O 8 Cl 18 (3.44 eV), 28 Pb 13 O 6 Cl 4 Br 10 (3.05 eV), 47 Pb 13 O 6 Cl 7 Br 7 (3.13 eV), 47 Pb 13 O 6 Cl 9 Br 5 (3.21 eV), 47 Pb 18 O 8 Cl 15 I 5 (2.82 eV) 48 and CdPbOCl 2 (3.63 eV). 49…”

Cs2Bi2OSi2O7: A Promising Bismuth Silicate Nonlinear Optical Crystal with Face-Sharing BiO5 Polyhedra Exhibiting Strengthened Second Harmonic Generation Response and Birefringence

“…As presented in Figure a, the SHG signal of CBSO enhances along with the increasing particle sizes before it reaches the maximum value that implies phase-matching nature, as defined by Kurtz and Perry, and CBSO displays a strong SHG intensity of ∼3.5 × KDP in the particle size range of 180–212 μm (Figure b). Notably, the observed result of CBSO is comparable to that of the universally used practical crystal LBO (3 × KDP). , As deposited in Figure c, CBSO has an impressive UV cut-off edge of 279 nm and gives wide band gaps of 3.6 eV, which may be beneficial for reducing two-photon absorption, according to the previous studies. − The IR spectrum tests demonstrate that CBSO exhibits no obvious absorption in a broad range of 4000–1045 cm –1 (Figure d); thus, CBSO is transparent in a wide region over 3–5 μm based on the two-phonon approximation, which is favorable for mid-IR NLO applications Table S3 lists the absorption bands and assignments of CBSO. , …”

Crystallographic Insights into the Crystal Structure and Intrinsic Properties of Ca12Al14O33-Type Rb3LiZn2(MoO4)4Single Crystals

“…In general, this method gives a lower boundary for the band-gap energy due to the presence of an Urbach tail . As previously reported, such a wide band gap is suggested to be beneficial to generate a high laser-damaged threshold . The transmission spectra of RLZM were obtained based on a regular wafer with a thickness of 1 mm.…”