Shanghai Institute of Optics and Mechanics proposes a new solution for quartz glass as a visible light laser material

Recently, Hu Lili, a research group of the Advanced Laser and Optoelectronic Functional Materials Department of the Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, proposed a new scheme based on rare earth ions Dy3+doped quartz glass as a yellow laser material, and the relevant research results were published in the Journal of the American Ceramic Society as "Effect of P/Al ratio on the X ray induced darkness in Dy doped silica glasses at visible wavelengths".

At present, Dy3+doped yellow light lasers have important application potential in fields such as Bose Einstein condensation and photocoagulation therapy. Fluoride fiber matrix is widely used as the main material for visible light gain fibers due to its low phonon distribution. However, fluoride optical fibers have limitations such as poor chemical stability and mechanical properties, as well as harsh preparation conditions, which greatly increase the cost and difficulty of preparation. In contrast, quartz glass matrix has achieved rapid development due to its excellent physical and chemical properties, mechanical properties, and optical properties, and has successfully achieved yellow light laser output of Dy3+ions. However, Dy3+doped quartz fibers suffer from photon darkening under blue light excitation, which limits the further improvement of output power. Therefore, how to suppress light dimming has become a key scientific problem that urgently needs to be solved in the field of visible light lasers.

The research team proposes a new scheme for anti photon darkening Dy3+doped quartz glass. This scheme significantly reduces the absorption loss caused by irradiation by increasing the P/Al ratio, suppressing the valence change of Dy ions and the formation of defects such as Al OHC from within the glass matrix. In quartz glass, Al is a commonly used rare earth ion dispersant that can improve the dispersion and solubility of rare earth ions. However, due to the mismatch between the valence state of Al3+in quartz glass and the matrix Si, defects such as hole center Al-OHC are easily generated after absorbing a certain amount of energy (blue light, ultraviolet radiation). The introduction of P can form a valence equilibrium and stable [PAlO4] structural group with Al, which suppresses the formation of Al related defects and improves the anti darkening performance of Dy doped quartz glass. This work provides key materials and method support for visible light fiber lasers.

The relevant research has been supported by projects such as the National Natural Science Foundation of China.

Figure 1: Increasing the P/Al ratio suppresses defects induced by irradiation in quartz glass

Source: Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences