Laser-induced damage in focus
The transformation of infrared light to a different wavelength, such as visible light, is important in many applications. Some of the most efficient semiconductor lasers operate in the infrared region of the spectrum, whereas many useful applications of laser light, such as laser surgery or spectroscopy, require light of a different wavelength. The most efficient way to convert light into different wavelengths is to use nonlinear optical crystals, but these tend to suffer crystal damage at high laser intensities. Oleg Louchev from the RIKEN Center for Advanced Photonics and colleagues have now discovered that such crystal damage arises from small localized temperature rises due to photon absorption and electric field effects within the crystal.