2D Ductile Transition Metal Chalcogenides (TMCs): Novel High‐Performance Ag₂S Nanosheets for Ultrafast Photonics

Abstract

As a member of the 2D transition metal chalcogenides (TMCs), 2D Ag2S with large absorption coefficient, broadband optical response, extraordinary metal‐like ductility, high plastic deformation strain, unique layered structure, and very low solubility has offered a platform for achieving tremendous success in various fields. Great achievements have been made in exploring the linear optical, mechanical, and photoelectric properties of 2D Ag2S nanosheets. However, the nonlinear optical properties of 2D Ag2S nanosheets and their applications in ultrafast photonics have not been studied. The saturable absorption property of 2D Ag2S nanosheets is experimentally illustrated at the telecommunication band with a large optical modulation depth of 15.5% and a low saturable intensity of 250.4 MW cm−2. Moreover, the 229th harmonic soliton molecule with repetition rate of 1.1 GHz based on 2D Ag2S saturable absorber is realized at the telecommunication band for the first time to the authors' knowledge. Thankfully, 2D Ag2S nanosheets display excellent nonlinear optical properties suggesting that this may open a new door for advanced photonic devices based on 2D Ag2S nanosheets.

High-Pressure Behaviors of Ag2S Nanosheets: An in Situ High-Pressure X-Ray Diffraction Research

“…As a well-known metal sulfide, Ag 2 S is a direct narrow band gap semiconductor (~1.5 eV), with high absorption coefficient (10 4 m −1 ), good chemical stability and optical properties [ 1 , 2 , 3 ]. So far, Ag 2 S materials have been extensively synthesized and studied due to their important applications including semiconductors, photovoltaic cells, infrared detectors, photoelectric switches and oxygen sensors [ 4 , 5 , 6 ]. Recently, the phase transitions of Ag 2 S have attracted much attention and a lot of research has been conducted around this topic.…”

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

“…Especially, graphene has enormously promoted the development of mode-locked lasers due to its properties of wide absorption range, low saturation intensity, ultrafast recovery time and high damage threshold [12][13][14][15]. Under the encouragement of graphene, similar findings in other 2D nanomaterials such as topological insulators (TIs) [17][18][19][20], transition metal dichalcogenides (TMDs) [21][22][23][24][25][26][27][28][29][30][31][32][33][34], black phosphorus [35][36][37], MXenes [38,39], Xenes [40][41][42][43][44][45] and so on have been reported focusing their saturable absorption and laser propagation performance. Among them, TMDs exhibit significant essential applications in optoelectronic and biological fields [46][47][48].…”

Palladium selenide as a broadband saturable absorber for ultra-fast photonics

“…As is known, the zero-bandgap structure of graphene also brought great obstacles to its optoelectronic device applications. Since then, inspired by graphene, various 2D layered materials including multielemental (transition metal dichalcogenides (TMDs) [30][31][32][33][34][35][36][37][38][39][40][41], topological insulator (TIs) [42][43][44][45][46][47], ferromagnetic insulator (FIs) [48][49][50], metal chalcogenide [51,52], MXenes [53][54][55][56], etc.) and mono-elemental (Xenes (phosphorene [57][58][59][60][61][62][63][64][65][66], graphdiyne [67], antimonene [68], bismuthene [69][70][71], tellurene [72,73]) and selenene [74]) were prepared as mode lockers for obtaining pulsed fiber lasers extensively.…”