A Hybrid Halide Perovskite Birefringent Crystal

Abstract

Birefringent crystals that can modulate the polarization of light play a significant role in modern optical devices including polarizing microscopes, optical isolators, and achromatic quarter‐wave plates. To date, commercial birefringent crystals are exclusively limited to purely inorganic compounds. Here we report a new organic–inorganic hybrid halide, MLAPbBr4 (MLA=melamine), which features a (110)‐oriented layered perovskite structure. Although the 6s2 lone‐pair electrons of Pb2+ cations are stereochemically inert, MLAPbBr4 exhibits a birefringence of 0.322@550 nm, which exceeds those of all commercial birefringent crystals. The first‐principles calculations reveal that this birefringence should be ascribed to the highly dislocated π‐conjugation of MLA cations and high distortion of PbBr6 octahedra. This work highlights the persistently neglected great potential of hybrid halide perovskites as birefringent crystals.

[C(NH2)3]2MoO2F4·H2O: Unique Chinese-Knot Structure Revealing Superior Nonlinear-Optical Properties

“…Furthermore, there is no apparent absorption peak in the wavenumber region of 750–900 cm –1 , indicating that there is no Mo–O–Mo bond in the structure of GMOF, confirming that the title compound features a 0D MoO 2 F 4 cluster structure. All of the distinctive absorption peaks of organic and inorganic functional groups are consistent with other previously reported compounds. − …”

[C(NH2)3]BiCl2SO4: an excellent birefringent material obtained by multifunctional group synergy

“…Birefringent materials have attracted widespread academic and commercial interest in many branches of science and engineering, including the laser industry, optical communications, polarimetry, and scientific instrumentation, due to their ability to modulate the polarization of light. [1][2][3][4][5][6][7][8][9][10][11] Many birefringent materials, including YVO 4 , 12 TiO 2 , 13 CaCO 3 , 14 LiNbO 3 , 15 MgF 2 16 and α-BaB 2 O 4 17 crystals, have been discovered and widely used in the production of optical devices, such as phase compensators, polarizers, polarization beam displacers and circulators. However, these known birefringent materials are not conducive to the development of optical device miniaturization due to their inherent flaws, such as difficulties in the growth of high-quality CaCO 3 crystals, low transmittance of YVO 4 below 400 nm, and the relatively small birefringence of MgF 2 and α-BBO.…”

SbHPO3F: 2D van der Waals Layered Phosphite Exhibiting Large Birefringence

“…Owing to the ability of modulating polarized light, birefringent materials are expected to play an important role in the fabrication of polarizing devices, such as optical polarization, optical modulation, optical communication, and nonlinear optical (NLO) technology. − So far, several birefringent materials have been commercialized, e.g., calcite (CaCO 3 ), α-BaB 2 O 4 (α-BBO), YVO 4 , and MgF 2 crystals. Nevertheless, due to inherent defects such as narrow transparent region, small birefringence, and poor crystal quality, their wide application is severely limited.…”