Mode and Wavelength-Switchable Pulsed Fiber Laser With Few-Mode Fiber Grating

Abstract

We propose and demonstrate a mode and wavelength-switchable pulsed fiber laser using two-mode fiber Bragg grating (TM-FBG) as both transverse mode converter and wavelength selector. The mode-locking mechanism is based on saturable absorption of semiconductor saturable absorption mirror (SESAM). Due to the use of low polarization-dependent mode-locking method, polarization disturbation between mode-locking and transverse-mode selection has been effectively eliminated, thus enabling flexible transverse-mode selection with simultaneous mode-locking operation. Moreover, through the optimized offset launching technique, this laser can operate at the wavelengths of the fundamental mode (LP01) and second-order mode (LP11), and thus export cylindrical vector beams (CVBs) and fundamental mode beams at the TM-FBG output port, respectively. This all-fiber laser is a simple, low-cost and flexible source for mode-division multiplexing system and other applications.

Generation of burst pulses through multimodal interference in a passively mode-locked ytterbium fibre-ring laser

“…That means, for a single pulse in figure 2(a), it was observed a centred wavelength of 1038 nm, H1 position in figure 3, and so on. Similar experimental results have been reported by Cai et al in [22], who achieved a switching mode by mechanically align a couple of fibre cores. Another approach has been proposed by Wright et al [26], where a multi-mode fibre is used to produce spatiotemporal mode-locking, and the wavelength filtering is made by bulk components.…”

“…Furthermore, burst of pulses have been reported at emitting in a fixed central wavelength. Hence, little empirical research on the multiple-wavelength operation from a PMLFL has been carried out [22].…”

High-power fiber laser with real-time mode switchability

“…In fact, there are several approaches to realizing mode adjusting/switching in fiber lasers [12] , and technically an 'optical switch' combined with mode selective components should be adopted. The mode switching/adjusting operation could either be realized by real optical components, such as acoustic-optic tunable filter (AOTF) [13] , special fiber coupler [14][15][16][17] , acoustically induced fiber grating (AIFG) [18][19][20][21] , polarization controller (PC) [22][23][24][25][26][27] , and spatial light modulator [28] , or by some physical mechanisms, such as temperature control of few-mode fiber Bragg gratings (FBGs) [29] , altering the excitation condition [30] , and injection locking [31] . However, fast mode switching between different transverse modes in fiber lasers has only been demonstrated using AOTF and AIFG.…”