Powerful Q-switched Raman laser at 589 nm with a repetition rate between 200 and 500 kHz.

We demonstrate a highly powerful acousto-optically Q-switched Nd:YVO4 yellow laser at 589 nm by using a Np-cut KGW crystal and a phase-matching lithium triborate crystal to performance the intracavity stimulated Raman scattering and second-harmonic generation, respectively. We experimentally verify that the design of the separate cavity is superior to the conventional design of the shared cavity. By using the separate cavity, the optical-to-optical efficiency can be generally higher than 32% for the repetition rate within 200-500 kHz. The maximum output power at 589 nm can be up to 15.1 W at an incident pump power of 40 W and a repetition rate of 400 kHz.

High-power diode-pumped Nd:GdVO4/KGW Raman laser at 578 nm.

A diode-pumped neodymium-doped gadolinium vanadate (Nd:GdVO4) laser is developed as a compact efficient yellow light at 578 nm by means of intracavity stimulated Raman scattering (SRS) in a potassium gadolinium tungstate (KGW) crystal and the second-harmonic generation in a lithium triborate crystal. The SRS process with a shift of 768cm-1 is achieved by setting the polarization of the fundamental wave along the Ng axis of the KGW crystal. The self-Raman effect arising from the Nd:GdVO4 crystal is systematically explored by employing two kinds of coating specification for the output coupler. With a specific coating on the output coupler to suppress the self-Raman effect, the maximum output power at 578 nm can reach 3.1 W at a pump power of 32 W. Moreover, two different lengths for the Nd:GdVO4 crystal are individually used to verify the influence of the self-Raman effect on the lasing efficiency.

Efficient solid-state Raman yellow laser at 579.5 nm.

A highly efficient diode-pumped Nd:YVO4/KGW Raman yellow laser is developed to produce a 6.8 W yellow light at 579.5 nm accompanied by a 3.2 W Stokes wave at 1159 nm under an incident pump power of 30 W. The intracavity stimulated Raman scattering with the shift of 768cm-1 is generated by setting the polarization of the fundamental wave along the Ng direction of an Np-cut KGW crystal. The Nd:YVO4 gain medium is coated as a cavity mirror to reduce the cavity losses for the fundamental wave. More importantly, the KGW crystal is specially coated to prevent the Stokes wave from propagating through the gain medium to minimize the cavity losses for the Stokes wave.

Exploiting a monolithic passively Q-switched Nd:YAG laser to mimic a single neuron cell under periodic stimulation.

A monolithic passively Q-switched Nd:YAG laser under periodic pulse pumping is originally exploited to emulate the response of a single neuron cell stimulated by periodic pulse inputs. Experimental results reveal that the output characteristics of the monolithic passively Q-switched laser can analogously manifest not only the firing patterns but also the frequency-locked plateaus of the single neuron cell. Moreover, the sine circle map is innovatively used to generate the output pulse sequences that can exactly correspond to experimental firing patterns. The present exploration indicates that a monolithic passively Q-switched solid-state laser is highly feasible to be developed as a compact artificial neuron cell.

Compact efficient high-power triple-color Nd:YVO4 yellow-lime-green self-Raman lasers.

A novel, to the best of our knowledge, approach is developed to realize a high-power compact efficient yellow-lime-green triple-color ${\rm Nd}:{{\rm YVO}_4}$Nd:YVO4 self-Raman laser. The 588 nm yellow laser, the 559 nm lime laser, and the 532 nm green laser are converted from the 1064 nm fundamental wave and the 1176 nm Stokes Raman field. The simultaneous three-color operation is accomplished with three stages to step-by-step generate the 588 nm, 559 nm, and 532 nm lasers by using three different lithium triborate (LBO) crystals. By tuning the temperature of each individual LBO crystal, the 588 nm, 559 nm, and 532 nm output powers can be nearly the same and concurrently up to 2.4 W at the incident pump power of 30 W, corresponding to a conversion efficiency of 24% for the total output power.