Optical anisotropy of one-dimensional perovskite C₄N₂H₁₄PbI₄ crystals

Abstract

Optical anisotropy is essential for the polarization-sensitive optoelectronic devices. Recently, in-plane anisotropy is demonstrated in various 2D layered materials. It has been proved that organic-inorganic perovskites possess excellent optical properties; however, the anisotropy of organic-inorganic perovskites is rarely reported because of the in-plane isotropic structure. Here, we report a large optical anisotropy of one-dimensional organic lead iodine perovskites C 4 N 2 H 14 PbI 4 crystals, including emission, excitation and reflection anisotropy. An emission linear dichroic ratio of 5.5 and an excitation linear dichroic ration of 7 are achieved respectively, which are much larger than the inplane anisotropy of 2D layered materials. The large optical anisotropy can be ascribed to the anisotropic dipole moment in the unique 1D chain structure. In addition, the PL of the 1D C 4 N 2 H 14 PbI 4 crystal is dominated by the broadband self-trapped exciton emission due to the quantum confinement effect and strong electron-phonon interaction. Our results advocate that 1D perovskites are promising in the application of broadband polarization-sensitive optoelectronic devices.

A first-principles study of exciton self-trapping and electric polarization in one-dimensional organic lead halide perovskites

“…[4][5][6][7][15][16][17] For instance, strong broad emissions were observed in 1D-C 4 N 2 H 14 PbX 4 (X = Cl, Br and I) at low temperatures, which have been attributed to the formation of STEs. [17][18][19][20] Despite some encouraging results obtained via experiments and theory, further optimization of the exciton luminescence properties is limited, largely due to the lack of microscopic understanding of the exciton behavior. Therefore, clarifying the self-trapping mechanism and their nature is of great significance to further improve the photoluminescence efficiency of 1D-C 4 N 2 H 14 PbX 4 .…”

Broadband strong optical dichroism in topological Dirac semimetals with Fermi velocity anisotropy*

“…This implies that at an appropriately chosen frequency, dielectric (e.g., waveguide modes) or metallic (SPPs) behavior can dominate depending on the direction of the incident light, thus opening up a novel device architecture where both the strength and the nature of light-matter interaction could be tailored using incident light polarization. We further remark that linear dichro-ism of 3D DSMs with Fermi velocities anisotropy is substantially stronger than many anisotropic optical materials as shown in Table II [64][65][66][67][68][69][70][71][72][73][74]. Although the extinction ratio is dwarfed by other exceptionally strong anisotropic optical materials, such as bilayer tellurene [73], and antimonene, the broadband linear dichroism of Cd 3 As 2 and Na 3 Bi represents a unique strength not found in bilayer tellurene and antimonene.…”

Anisotropic Low‐Dimensional Materials for Polarization‐Sensitive Photodetectors: From Materials to Devices

“…In 1D perovskites, linear dichroism has also been observed. [157,158] The behavior may be ascribed to the different selection rules of the parallel energy bands and the anisotropic dipole moment of the 1D structure.…”