Cs₂ZnSn₃S₈: A Sulfide Compound Realizes a Large Birefringence by Modulating the Dimensional Structure

Abstract

Birefringence, an important optical performance parameter for optoelectronic functional materials, is mainly influenced by the types of anion groups and their spatial arrangement. Inspired by the relationship between the structure and properties of chalcogenides, combined with the dimensional transformation, we successfully synthesized a sulfide compound (Cs2ZnSn3S8) with a two-dimensional layered structure and a large birefringence. The experimental results showed that, compared with Rb10Zn4Sn4S17, Cs2ZnSn3S8 achieved the structural transition from a zero-dimensional arrangement to a two-dimensional lamellar arrangement and achieved a breakthrough of birefringence from 0 to 0.12, which was determined by both experiments and first-principles calculations. These findings demonstrated that Cs2ZnSn3S8 was a potential birefringent material and provided instructions for the study of the synthesis of birefringent materials.

Sharp Enhancement of Birefringence in Antimony Oxalates Achieved by the Cation–Anion Synergetic Interaction Strategy

“…According to the relationship between structures and their properties, the birefringence of a compound is a positive correlation with the optical anisotropic polarizability of the basic functional modules and their spatial arrangement. , Recently, several strategies have been developed to enhance the birefringence, such as the following: (1) Introducing anionic groups with planar π-conjugation, including BO 3 , CO 3 , NO 3 , B 3 O 6 etc . − For instance, Cs 2 Pb­(NO 3 ) 2 Br 2 exhibits a large birefringence of 0.147@546 nm, while Ba 2 Mg­(B 3 O 6 ) 2 displays a relatively large birefringence of about 0.116@589 nm . (2) Introducing distorted polyhedra based on cations with stereochemically active lone pairs (SCALP), such as Sn 2+ and Sb 3+ complexes. , For example, Sn 2 B 5 O 9 Br exhibits an extremely large birefringence of 0.439@546 nm attributed to the SnO 7 Br 2 polyhedra .…”

NaBaBS3: A Promising Infrared Functional Material with Large Birefringence Induced by π-Conjugated [BS3] Units

“…53 Compared with them, the birefringence of NaBaBS 3 is larger, which indicates that [BS 3 ] is satisfactory to form large optical anisotropy. 53 Many reported metal sulfides are known to exhibit large birefringence but their band gap is relatively small such as Na 7 ZnSb 5 S 12 (0.30 at 1064 nm, 2.23 eV), Na 7 CdSb 5 S 12 (0.32 at 1064 nm, 2.18 eV), Na 7 HgSb 5 S 12 (0.37 at 1064 nm, 2.03 eV), 83 and Cs 2 ZnSn 3 S 8 (0.12 at 1064 nm, 2.82 eV), 84 unfavorable for the high LIDT. On the other hand, some metal sulfides that have large band gaps display small birefringence such as Li 4 MgGe 2 S 7 (4.12 eV, 0.033 at 1064 nm), 85 Ba 6 Zn 7 Ga 2 S 16 (3.5 eV, 0.036 at 1064 nm), 86 and BaGa 4 S 7 (3.54 eV, 0.04 at 1064 nm).…”

Tailored Ordered Structures with Functional Units of Distorted [NbO6] and Antiparallel [GeO4] for Enhanced Birefringence in Germanate Crystal

“…For practical applications, a good birefringent crystal should simultaneously satisfy several prerequisites including relatively large birefringence (∆n > 0.1), wide transmission region, superior laser damage threshold (LDT), excellent thermal and chemical stability, and facile crystal growth. [16][17][18] Among them, two key aspects, birefringence and transmission region are determined by the electron and phonon response to external electro-magnetic field, respectively. Therefore, both electron and phonon tailoring is necessary for rational birefringent crystal design.…”