Palladium diselenide as a direct absorption saturable absorber for ultrafast mode-locked operations: from all anomalous dispersion to all normal dispersion

Abstract

Layered transition metal dichalcogenides with excellent nonlinear absorption properties have shown remarkable performance in acting as ultrafast photonics devices. In our work, palladium diselenide (PdSe2) nanosheets with competitive advantages of wide tunable bandgap, unique puckered pentagonal structure and excellent air stability are prepared by the liquid-phase exfoliation method. Its ultrafast absorption performance was verified by demonstrating conventional and dissipative soliton operations within Er-doped fiber lasers. The minimum pulse width of the conventional soliton was 1.19 ps. Meanwhile, dissipative soliton with a 46.67 mW output power, 35.37 nm spectrum width, 14.92 ps pulse width and 2.86 nJ pulse energy was also generated successfully. Our enhanced experiment results present the excellent absorption performance of PdSe2 and highlight the capacity of PdSe2 in acting as ultrafast photonics devices.

Impact of Pauli-blocking effect on optical limiting properties of WSe2 thin films

“…7(c)). Consequently, the two-photon transition probability reduce as a result of non-availability of states in the relevant CB which is alternately termed as Pauliblocking effect [55,56]. Due to the weak two-photon absorption process, the transmission of the films (near the focus) is more than that for regions far-from-focus which could be observed in Fig.…”

Ultrafast fiber laser at 1570 nm based on organic material as saturable absorber

“…Along the development of saturable absorber, many materials have been reported to induce mode-locking operation in fiber laser system, including TMDs 45 – 50 , TIs 51 – 53 , MXene 54 and other emerging materials 55 – 58 . These materials have proven the capability to induce ultrafast phenomena, ranging from picosecond down to femtosecond.…”

Passively Mode-Locked Er-Doped Fiber Laser Based on Sb2S3-PVA Saturable Absorber

“…Compared with Q-switching, mode-locking attracted more considerable attention because of narrower pulse width and higher peak power. Recently, various kinds of two-dimensional (2D) materials, such as graphene [ 8 , 9 ], graphene oxide (GO) [ 10 ], MXenes [ 11 ], single-walled carbon nanotubes (SWCNTs) [ 12 ], quantum wells (QWs) [ 13 ], black phosphorus (BP) [ 14 ], topological insulators (TIs) [ 15 , 16 , 17 ], transition metal dichalcogenides (TMDCs) [ 18 , 19 , 20 , 21 , 22 , 23 , 24 ], and layered metal sulfides (LMSs) [ 25 ] were widely used as saturable absorbers in mode-locked fiber lasers due to their outstanding nonlinear saturable absorption properties caused by sub-band gap absorption or the Pauli blocking principle [ 26 ]. In particular, various TMDCs including MoS 2 [ 19 ] and WS 2 [ 21 ], etc.…”