Q-switched giant pulsed erbium-doped all-fiber laser with V_(2)ZnC MAX phase saturable absorber

MXenes,drawn from MAX phases,are special two-dimensional substances with numerous advantages in nonlinear optics,specifically in giant and ultrashort pulsed-laser applications.Ti_(3)C_(2)T_(x)and Ti_(2)CT_(x)nanosheets however rapidly deteriorate under ambient conditions,limiting their applications.This paper demonstrates how excellent modulation depth of one of the MAX phase compounds vanadium zinc carbide(V_2ZnC)makes it a brilliant saturable absorber(SA)in passively Q-switched all-fiber pulsed lasers,integrated such that a 16.73-μm V_(2)ZnC-polyvinyl alcohol(PVA)thin film acts as SA in the laser.Saturable and non-saturable absorptions were found to be 13.2%and 10.47%,while saturation optical intensity and modulation depth were 6.25 k W/cm^(2)and 12.43%,respectively,illustrating the optical nonlinearity.The superiority of MAX-PVA,fabricated in four distinct ratios,was demonstrated by the fact that it self-starts a giant pulsed laser at pump power as low as 22.5 mW and firmly accomplished 120.6 kHz repetition rate with a pulse width of 2.08μs.It is a fine SA for the use of pulsed-laser production using all-fiber laser due to fabrication simplicity and great optical,thermophysical,and mechanical qualities.

Ti_(3)AlC_(2) coated D-shaped fiber saturable absorber for Q-switched pulse generation

In this letter,a titanium aluminum carbide(Ti_(3)AlC_(2))coated D-shaped fiber is proposed and demonstrated as a new saturable absorber(SA)for Q-switched laser pulse generation.In preparing the SA,the TiAlCpowder is dispersed in liquid polyvinyl alcohol(PVA)before the solution is dropped and left to dry onto a polished surface of D-shape fiber.The SA is added to an erbium-doped fiber laser(EDFL)cavity to modulate the cavity loss for Q-switching.The Q-switched laser is obtained at 1561 nm.The pulse width of the pulses can be varied between 7.4μs and 5.1μs with a corresponding repetition rate range from 41.26 k Hz to 54.35 k Hz,when the pump power is increased from 42.2 m W to 71.5 m W.At 71.5 m W pump,the pulse energy is obtained at 70.3 n J.The signal-to-noise ratio(SNR)of the fundamental frequency is recorded at 67 d B,which indicates the stability of the laser.