ChemInform Abstract: Phase Equilibrium Studies in the PbTe—Ga₂Te₃ and PbTe—In₂Te₃ Systems for Growing New Nonlinear Optical Crystals of PbGa₆Te₁₀ and PbIn₆Te₁₀ with Transparency Extending into the Far‐IR.

Abstract

Nonlinear crystals of the title compounds, which are transparent into the mid‐ and far‐infrared spectral range to beyond 30 μm are grown and their linear and nonlinear optical properties are determined.

Ba6In2Ge2Te15: a THz birefringent material with an intriguing quasi-[Te5]4− chain possessing large optical anisotropy and an ultrawide transmission range

“…3b). 28,32,42,43 The reason why the title compound exhibits a wide transmission range is as follows: In general, the frequency of lattice vibrations depends on the atomic mass and the bond length negatively. The heavier the atom and longer the bond length in the crystal, the lower the vibrational frequency will be.…”

“…M III Te 4 and M IV Te 4 (GaTe 4 , InTe 4 , GeTe 4 , SnTe 4 , and PbTe 4 ) tetrahedra have been illustrated to be valuable structural groups. [30][31][32] In our previous work, β-BaGa 2 Te 4 with GaTe 4 tetrahedra exhibited large birefringence (0.325 @2050 nm). In addition, M IV elements have various valence states (+2, +3, +4) and flexible bonding modes, which may increase the structural diversity and hence the chance of achieving improved properties.…”