HgBrI: A promising nonlinear optical material in IR region

This paper reports the second-order nonlinear optical (NLO) property of HgBrI for the first time. The compound was re-synthesized with a new synthetic method by combining the individual solution of stoichiometric amounts of HgBr2 and I2 in acetone. The compound exhibits a strong phase-matchable second harmonic generation (SHG) property about 1.4 times stronger than KTiOPO4 (KTP) based on the powder SHG measurement. It also shows wide transparency in the infrared region from 0.46 to 40 μm and good thermal stability with decomposition temperature at about 200 °C. All these properties indicate that HgBrI is a promising new candidate for NLO materials in the IR region.