Acousto-optically Q-switched cavityless weak-feedback laser based on Nd:GdVO₄bounce geometry

Abstract

An AOQ (acoustic-optic Q-switched) laser with cavityless weak-feedback configuration is demonstrated based on a Nd:GdVO4 bounce geometry. The laser can operate at a repetition up to 500 kHz with the output power above 4W. The pulse-width at 100 kHz reaches 5.2 ns, which is 4.3 times the round-trip time. A theory of Q-switched cavityless weakfeedback laser is proposed for the first time, to our best knowledge. This theory is very suitable for analyzing short pulses comparable to round-trip time. By utilizing the theory, simulation is implemented for our experimental conditions. The consistence between the simulation and the experimental results proves the validity of our theory.

Research Status of Amplified Spontaneous Emission Sources based on Doped Materials

“…And it is measured under the highest pump energy of 5.9J, with the beam quality in the slab thickness/width direction being ~3.5/17. bounce geometry [15]. Nd:GdVO 4 has higher slope efficiency than Nd:YAG, and better thermal conductivity as well as higher output power than Nd:YVO 4 .…”

“…Although there have been teams that have studied the rebound geometry of Nd:YVO 4 and Nd:YAG, there are few reports on the study of cavity-free switched-mode lasers. In 2019, R. Guo et al realized acoustically 𝑄-switched (AOQ) cavityless laser with weak feedbacks based on Nd:GdVO 4bounce geometry[15]. Nd:GdVO 4 has higher slope efficiency than Nd:YAG, and better thermal conductivity as well as higher output power than Nd:YVO 4 .…”

The modelling of power plant’s evaporative cooling tower operation taking into account hydrometeorological conditions

“…In most research works, the problem of cooling towers is regarded only as technical [6][7][8][9]. Basic research is practically absent.…”

“…The solving of the problem of ensuring the effective operation of cooling and restoring hot water temperature coming out of the condensers of power plant turbines is considered in the literature about cooling towers as purely technical task without peculiarities of non-equilibrium and non-linear phenomena inherent in mass, heat and momentum transfer processes in coupled hydrodynamic systems of inhomogeneous media [6][7][8][9]. The paper aims are to perform a numerical simulation of the evaporative cooling tower operation based on the developed mathematical algorithm [10], highlighting the influence of turbulent vortex motions on the air cooling of circulating water in evaporative tower large-scale cooling towers of power plants, considering changing hydrometeorological conditions.…”