[Hg3Se2]2- cluster drives giant optical anisotropy and broad infrared transparency

Optical anisotropy, a fundamental physical property for polarization control, has long presented a critical consideration in the development of optical materials, particularly in terms of its modulation mechanisms and performance optimization. In the mid- to far-infrared region, simultaneously achieving large birefringence and broad transparency within a single material remains a major challenge. Herein, we report the synthesis of Hg18Ga8Se8Cl32 (HGSC), a crystalline material featuring linear [Hg3Se2] structural units. HGSC demonstrates a large birefringence of 0.871 at 546 nm, accompanied by the broadest transparency window among Hg-based chalcogenide single crystals (0.4 to 25 µm). Theoretical calculations…

• NN
  National Natural Science Foundation of China

  Awards: 22335007, 22361132544, 62305382, 52302011
• CP
  China Postdoctoral Science Foundation

  Award: 2024T170994