Researchers reveal nonlinear optical mechanism of β-BaB2O4 by experimental electron density

As a well-known ultraviolet (UV)-vis-near-infrared (IR) nonlinear optical (NLO) material in the borate system, β-BaB2O4 (BBO) has a wide range of applications because of its outstanding NLO performance. Further analysis of the electronic structure of BBO is warranted to clarify the disputes on the second harmonic generation (SHG) mechanism and NLO functional motifs of BBO.