Bismuth germanate (Bi₄Ge₃O₁₂ or BGO) has been extensively studied because its interesting luminescent properties, like short decay time, photo, radioluminescence and the two-photon absorption property under the high-power laser at the wavelength of visible waveband. These properties make BGO suitable to be applied as scintillators in medicine, in geological explorations, nuclear physics, high energy physics and nonlinear optical field.

BGO Scintillator Crystal—A crystal used for high energy physics with nonlinear effects

As a novel generation of scintillation crystals, BGO shows the superior characteristics including high density, well chemical resistance, fine energy resolution, large refractive index, non-hygroscopic nature and high mechanical strength, which make it utilized in high energy physics experiments like the large electron-positron collider in CERN. It is worth noting that the BGO scintillating crystals as the direct medium for the possible annihilation of dark matter (energetic electrons and gamma rays) play an important role in the dark matter detection. In addition, compared with conventional nonlinear optical crystals, BGO exhibits three- and five-order non- linear absorption response in the visible and infrared optical band, respectively. It performed as well as the other excellent nonlinear optical materials in the nonlinear optical field due to its large nonlinear coefficient. Besides, as the typical photorefractive crystal, BGO crystal is of certain interest in view of its diverse application in opto- electronics and laser physics, such as four-wave frequency mixing and optical switching.