Negative Thermal Expansion of Mercurous Halides

Growth and Temperature-Dependent Mechanical and Thermal Properties of One-Dimensional Chain Structure Hg2Br2 Crystals for Infrared Acousto-Optic Device Application

“…Kim et al reported that the mercurous halide crystal has high transmittance in a wide spectral transmission range, and it exhibits positive thermal expansion along a-axis, while negative thermal expansion along c-axis. 18 Cho et al deeply analyzed the effect of the ampoule position, the temperature gradient, and the temperature of the bottom heater on the nucleation and crystal growth by using the experiment and simulation. 12 Our group also reported that the temperature field, growth rates, and vapor transport distances are key factors for obtaining high-quality crystals.…”

“…As early as 1970’s, Barta et al reported the growth, the polarizer design, and physical properties such as refractive indices, microhardness, and acoustical velocity of Hg 2 Cl 2 and Hg 2 Br 2 crystals. − Since 2005, Singh et al and Kim et al mainly reported the growth of mercurous halide family crystals and the design and fabrication of acousto-optic devices. ,, Very recently, mercurous halides have drawn renewed attention mainly due to their unique optical, acoustic, and thermal properties. Kim et al reported that the mercurous halide crystal has high transmittance in a wide spectral transmission range, and it exhibits positive thermal expansion along a -axis, while negative thermal expansion along c -axis . Cho et al.…”