Stable pulse-compressed acousto-optic Q-switched fiber laser

Abstract

A novel acousto-optic switch operation by a simple laser-diode pumped acousto-optic, Q-switched, ytterbium-doped, double-clad fiber laser is reported. Stable compressed Q-switched sub-40 ns pulses with a beam quality factor (M(2)=2) are achieved at the repetition rate of 1-50 kHz. Q-switched pulses of ~20 microJ pulse energy and 35 ns pulse width are obtained at the repetition rate of 50 kHz. Finally, a reasonable explanation of the novel Q-switched operation is presented.

Tunable passively Q-switched thulium-doped fiber laser operating at 1.9 μm using arrayed waveguide grating (AWG)

“…In contrast with an earlier demonstration by H. Ahmad et al and M. T. Ahmad et al [37,38], the demonstration of the passively Q-switched output using graphene and MWCNT at operating wavelength of 2.0 mm has a lower maximum repetition rate of around 16.0 kHz and 21.0 kHz respectively compared to our experiment which has a maximum value of 68.3 kHz at 1871.6 nm. Moreover, all the tuned wavelengths in this demonstration have also higher maximum repetition rates compared to the mentioned works, which is about an average of 60 kHz.…”

“…in range-finding, remote-sensing and in the field of medicine [14]. Though Q-switching can be produced through active systems, the technique usually requires the application of an electric signal, applied to an acousto-optic or electro-optic modulator [15][16][17][18] -and can be rather complicated and costly as compared with passive Q-switching systems. Passively Q-switched fiber lasers offer the appealing advantages of compactness, simplicity, and flexibility in design.…”

Effect of temperature on refractive index match of laser glass edge cladding

“…For 632.8 nm, the refractive indices match well even though the temperature increases close to the polymer transition temperature (about 40 °C). For 1064 nm, the indices also match well below 30 °C, which is close to the temperature at the interface after laser shot because the appropriate absorption coefficient (3 -5 cm -1 ) of the Cu 2+ -doped cladding glass is adopted [22][23][24] . The polymer refractive index is lower than that of the laser glass when it is close to the polymer transition temperature.…”

Large-Size Crystal Growth and a Fiber-Coupled Acousto-Optic Device of TiTe3O8

“…5−8 The fiber acousto-optic Q-switch, 9,10 which can ensure an all-fiber structure, is usually used to generate high-energy pulse fiber lasers. 11,12 Compared with free space lasers, the polarization lasers have advantage in the fields of optical fiber sensing, signal processing, and coherent detection. 13−15 When the polarization laser propagates through the acousto-optic Q-switch without polarization-maintaining ability, the continuous laser can be changed to pulse laser.…”