MXene/Graphene Oxide Heterojunction as a Saturable Absorber for Passively Q-Switched Solid-State Pulse Lasers

Abstract

Owing to their unique characteristics, two-dimensional (2-D) materials and their complexes have become very attractive in photoelectric applications. Two-dimensional heterojunctions, as novel 2-D complex materials, have drawn much attention in recent years. Herein, we propose a 2-D heterojunction composed of MXene (Ti2CTx) materials and graphene oxide (GO), and apply it to an Nd:YAG solid-state laser as a saturable absorber (SA) for passive Q-switching. Our results suggest that a nano-heterojunction between MXene and GO was achieved based on morphological characterization, and the advantages of a broadband response, higher stability in GO, and strong interaction with light waves in MXene could be combined. In the passively Q-switched laser study, the single-pulse energy was measured to be approximately 0.79 µJ when the pump power was 3.72 W, and the corresponding peak power was approximately 7.25 W. In addition, the generation of a stable ultrashort pulse down to 109 ns was demonstrated, which is the narrowest pulse among Q-switched solid-state lasers using a 2-D heterojunction SA. Our work indicates that the MXene–GO nano-heterojunction could operate as a promising SA for ultrafast systems with ultrahigh pulse energy and ultranarrow pulse duration. We believe that this work opens up a new approach to designing 2-D heterojunctions and provides insight into the formation of new 2-D materials with desirable photonic properties.

Ag/MXene Composite as a Broadband Nonlinear Modulator for Ultrafast Photonics

“…In previous works, MXene combined with other nanomaterials serving as SAs has been reported in Q-switched lasers, such as molysulfide, graphene oxide, and ferroferric oxide. − Herein, we utilized a kind of composite composed of Ag and MXene materials as SAs in ultrafast lasers, which has been demonstrated to have excellent saturable absorption property for the generation of pulses . When the electrons in MXene jump from valence to conduction band, the existence of Ag prolongs the lifetime of excited electrons in the conduction band of MXene, enhancing the bleaching effect on the valence band of MXene.…”

VTe2: Broadband Saturable Absorber for Passively Q-Switched Lasers in the Near- and Mid-Infrared Regions

“…Nonetheless, it suffers from certain drawbacks, including exorbitant manufacturing costs, a low damage threshold, and a narrow operating wavelength range, which reduces the corresponding flexibility and applicability . Relying on two-dimensional (2D) materials as SA is a cost-effective and compact method for generating short pulses via Q-switched in the NIR or MIR spectral ranges. − Due to their remarkable photoelectric properties, 2D materials have garnered significant attention for their potential applications as SA devices. − To date, extensive research has been conducted on PQS lasers utilizing 2D materials in the near-IR range, encompassing both 1.0 and 2.0 μm lasers. However, to advance the applications and progress of PQS lasers, it is of paramount importance to explore PQS lasers operating in the broadband spectrum.…”

Single-frequency linearly polarized Q-switched fiber laser based on Nb2GeTe4 saturable absorber

“…[26][27][28] As an alternative to SESAM, the other saturable absorbers such as twodimensional (2D) materials, specifically, topological insulators (TIs), 2D ternary tellurides, have attracted a lot of attentions due to the virtues of low cost and ideal nonlinear optical properties. [29][30][31] Li et al added a few-layer Bi 2 Se 3 (which is a kind of TIs) saturable absorber in the ring cavity to achieve passive Q-switching, and used an un-pumped erbium-doped fiber together with a 0.06-nm-bandwidth fiber Bragg grating as an ultra-narrow filter to obtain single-frequency pulsed laser with a central wavelength of 1550 nm and a pulse duration of 2.54 µs. [25] Compared with the Bi 2 Se 3 , the Nb 2 GeTe 4 , which is a kind of 2D ternary telluride, is more preferable for short pulse generation due to its lower saturation intensity and higher modulation depth.…”