High-power passively Q-switched 20 μm all-solid-state laser based on a MoTe₂ saturable absorber

Abstract

In this article, a high-power diode-end-pumped passively Q-switched (PQS) Tm:YAP laser is reported with novel two-dimension (2D) molybdenum ditelluride (MoTe) as a saturable absorber (SA). By using the open-aperture Z-scan method, the saturable absorption properties around 2.0 μm was characterized with a saturable fluence of 2.26 μJ∕cm and a modulation depth of 6.0% for the as-prepared MoTe SA. The band structure of MoTe with the introduction of Te vacancies is simulated by the DFT method, and the results indicate that the bandgap can be reduced with the vacancies in a suitable range. The shortest pulse width of 380 ns was obtained with an average output power of 1.21 W at a repetition rate of 144 kHz, corresponding to a maximum single pulse energy of 8.4 µJ and peak power of 22.2 W. It is the first presentation of MoTe as the saturable absorber in 2.0 μm solid-state pulse laser generation and the pulse width is the shortest among 2.0 μm solid-state lasers passive Q-switched with transitional metal dichalcogenides (TMDs) SAs to the best of our knowledge. The results indicated that MoTe should be an excellent optical modulator for high repetition rate and short pulsed laser generation in a broadband spectral range.

The energy band structure analysis and 2 μm Q-switched laser application of layered rhenium diselenide

“…As shown in Fig. 2(b), the ReSe 2 -SA was prepared with LPE method, which has been extensively applied in BP and other 2D materials [17][18][19]32 fabrication. This method enables large-scale exfoliation and uniform dispersion in the exfoliation medium.…”

“…Owing to possessing excellent saturable absorption properties and environmental stability, transition metal dichalcogenides (TMDs), which have layered structure of the X-M-X form (where M denotes a transition metal and X denotes a chalcogen), have been achieved encouraging results at 2-3 mm laser operations. [14][15][16][17][18][19] Rhenium diselenide (ReSe 2 ), one of the relatively unexplored members of the TMDs family, has attracted a signicant attention because of its unusual electronic and optical behaviors. [20][21][22][23][24] It crystallizes in a distorted octahedral (1T) diamond-chain structure at the triclinic symmetry.…”

Multi-Pulse Bound Soliton Fiber Laser Based on MoTe2 Saturable Absorber

“…Therefore, it is not suitable for communication applications. Meanwhile, layered MoTe 2 shows excellent saturable absorption [ 51 , 52 , 53 , 54 , 55 , 56 ] and high nonlinearity [ 57 , 58 ] (third-order nonlinear optical susceptibility is about 9.96 × 10 −11 esu) at longer wavelengths, which is suitable for the study of bound solitons.…”

High peak power passively Q‐switched 2 μm solid‐state laser based on a MoS2 saturated absorber

“…The two-dimensional material is confined to the twodimensional plane due to its carrier migration and thermal diffusion, which made the material exhibit many strange properties. Taking transition metal dichalcogenides (TMDs) as an example, [1][2][3][4][5][6][7][8] it has the characteristics of optical and electronic properties, which have aroused great interest in theoretical research and application. MoS 2 as a wide application of two-dimensional material is a kind of n-type block crystal, it had a larger surface within the carrier mobility (about 200-500 cm 2 V −1 s −1 ).…”