An actively Q-switched fiber laser with cylindrical vector beam generation

Abstract

We demonstrate an actively Q-switched fiber laser with cylindrical vector beam (CVB) emission using a few-mode fiber Bragg grating as the mode selection component and an acousto-optic modulator to achieve Q-switching. To the best of our knowledge, this is the first such demonstration. Using a linear cavity configuration, an actively Q-switched CVB with a pulse width of about 64 ns, a pulse energy of 4.25 µJ and a repetition rate of 20 kHz has been obtained. Moreover, by tuning the polarization controllers radially and azimuthally, polarized Q-switched beams can be excited separately with a polarization purity of >94.5%. This compact Q-switched fiber laser with ns CVB pulse output could find potential applications in the field of material processing, nonlinear optics and so on.

Actively Q‐switching an all polarization‐maintaining erbium‐doped fiber laser using an intracavity electro‐optic modulator

“…According to recent extant studies, piezoelectric actuators (PZTs), 14 acousto‐optic modulators (AOMs), 15 or electro‐optic modulators (EOMs) 16 can be used to produce actively Q‐switched lasers by quickly modulating the losses that occur between the cavities of a fiber laser which, in turn, affects the quality factor (Q‐factor) of its resonator. Actively Q‐switched lasers operating at 1 μm 17 to 1.5 μm 18 have been found to produce pulse durations of 64 ns and 429 ns, respectively. Nevertheless, only a handful of studies have examined using an all polarization‐maintaining (all‐PM) fiber laser cavity to produce actively Q‐switched laser pulses.…”

Broadband multi-channel quantum noise suppression and phase-sensitive modulation based on entangled beam

“…[7,8] However, an entangled light field in continuous variable has many advantageous such as superior broadband, excellent stabilization, and high operating efficiency. [9,10] The continuous variable of quantum entangled beam at 1550 nm communication band wavelength was produced by Feng et al [11] Wen et al proposed a scheme for tunable three-mode entanglement of continuous variable. [12] Two-mode entangled-state beams are applied within miniature waveguide circuits, which is a crucial step towards fully integrated quantum information.…”

Linear‐cavity mode‐locked fibre laser with cylindrical vector beam generation

“…Another commonly used mode excitation method is to include offset splicing between a SMF and a FMF to excite multiple higher order modes, together with an FMF Bragg grating (FM-FBG) to serve as a mode selector [14][15][16][17]. This method has been applied to quite a few fibre lasers including CW, Q-switched, and modelocked fibre lasers [18][19][20]. As a wavelength-selective reflection and mode-discrimination device, FM-FBG is especially suitable for constructing linear cavity fibre lasers.…”

“…Generally, compared with the ring-cavity fibre laser, the linear-cavity fibre laser is much simpler and more compact. So far, most of the works on CVB generation lay emphasis on the CVB pulse output from ring-cavity configuration, while few report on linear-cavity CVB pulse fibre laser [18][19][20]. On the other hand, there is no doubt that semiconductor saturable absorber mirror (SESAM) has been widely recognised due to its stability and reliability for ultrafast laser generation.…”