Advanced Solid-State Lasers: feature issue introduction.

This joint issue of Optics Express and Optical Materials Express features 23 peer-reviewed articles primarily by authors who participated in the Advanced Solid State Lasers conference, which was part of the Optica Laser Congress held in Tacoma, Washington, USA on October 8-12, 2023. This review provides a brief summary of these articles covering the latest developments in laser gain materials and nonlinear crystals, mode-locked lasers, fiber lasers and amplifiers, nonlinear optical sources, and novel concepts in laser design.

Rapid calculation of the efficiency of self-terminating four-level Q-switched lasers.

We have developed a simple approach to deriving the efficiency of Q-switched four-level lasers, valid even for arbitrarily long lower laser level lifetimes. By eliminating time dependence from the calculation, numerical solutions can be obtained very rapidly. Its threshold and limiting slope efficiency values provide useful estimates for free-running pulsed four-level lasers as well as Q-switched.

Enhanced mid-infrared emission of Pr ions in solids through a "3-for-1" excitation process - quantified.

Evidence is presented that a "three-for-one" process based on two cross-relaxations between Pr ions efficiently populates the mid-infrared-emitting H manifold in a Pr-doped low-maximum-phonon-energy host. The concentration dependence of infrared fluorescence spectra and lifetimes of polycrystalline Pr:KPbCl initially excited to the F manifolds indicate that the 3500-5500-nm fluorescence becomes strongly favored over shorter-wavelength infrared emission bands in the higher-concentration sample. The strong concentration dependence of the F and H manifold lifetimes suggests that both of these decay by cross-relaxation processes, resulting in more than one ion excited to H for each ion initially excited to F.

Cladding-pumped, Yb:YAG-core, fiber-like waveguide laser: modeling and experiment.

We developed a model describing the performance of the cladding-pumped, Yb:YAG-core, fiber-like waveguide laser with a large cladding-to-core area ratio. We analyzed how pump absorption and laser output efficiencies depend on the Yb-doping level as well as the waveguide parameters, such as clad-to-core area ratio and waveguide length. We also determined the conditions that maximize both pump and laser efficiency.

Pr:RbPbCl: temperature dependent spectra, dynamics and three-for-one excitation: erratum.

We present an erratum regarding the contents of Table 1.