Pulsed Solid-State Laser Systems Using ABCD Matrix Method: A Review
Y. S. Nada, J. M. El-Azab, S. M. Maize and Y. H. Elbashar
Although the laser diode and fiber laser are better than CW microchip lasers as they have the smallest size, compact design and wide range of emission laser wavelengths, the Q-switched solid-state microchip laser is better than laser diode and fiber laser, because the energy storage capacity and laser-induced threshold damage of laser diode are less than those of Q-switched microchip laser and long cavity of the fiber laser prevents achieving very short laser pulses. Yb:YAG was chosen as active medium due to its simple energy level scheme, long upper laser level lifetime (951 µs) which is suitable for storing energy, low quantum defects, large emission cross section, and large absorption cross-section for InGaAs laser emission. The combination of Cr4+: YAG and a doped-YAG gain medium, such as Yb:YAG, is particularly attractive from the point of view of an extremely robust device. Since both materials use the same host crystal, YAG, they can be diffusion-bonded to each other in a way that blurs the distinction between a monolithic and a composite-cavity device. Both materials have the same thermal and mechanical properties and the same refractive index, and the bond between them can be sufficiently strong that the composite device acts in all ways as if it were a single crystal. Due to better mechanical and thermal properties compared to the glass and single crystal, transparent ceramics became high power end-pumping lasers candidate in numerous fields. Ceramic active medium can be heavily and homogeneously doped with laser-active ions.
Keywords: ABCD Matrix, Pulsed lasers, laser systems, ultrashort pulse lasers