Graphdiyne as a Promising Mid‐Infrared Nonlinear Optical Material for Ultrafast Photonics

Abstract

fascinating physical and chemical properties. At present, two dimensional (2D) materials with brilliant nonlinear optical (NLO) properties play an key role in modern photonics since the appearance of graphene. [15] However, GDY, as a 2D allotrope of graphene, is still in the primary stage of its application in photonic fields. [16,17] On the basis of previous research results, the advantages of GDY as a NLO material for photonic devices are obvious. First, it is essentially different from the zero-band gap of graphene. GDY has a tunable direct band gap of 0.46-1.10 eV (according to different simulated methods), [18][19][20] which shows that GDY has great potential in the application of photonic devices based on optical switch function. Besides, in the structure of GDY, the alkyne bonds and sub-nanopore, provide a large number of reaction sites for its functionalization. In this context, the optical energy gap of the original GDY can be tuned in a wide range of wavelengths by controlling the type and amount of doped atoms (e.g., boron, nitrogen, phosphorus, and sulfur), [21][22][23] which makes GDY a more compatible NLO material. Recently, we used the method of spatial self-phase modulation to demonstrate the strong broadband Kerr nonlinearity and large nonlinear refractive index (in the order of ≈10 −5 cm 2 W −1 ) of GDY, [24] which indicates that GDY can be widely used in multi-functional photonic devices. Compared with the unstable black phosphorus (BP), the GDY material can remain stable up to 1000 K and its service life at room temperature is extremely long. [25] The excellent stability of GDY prevents it from photooxidation and photo degradation under high strong light irradiation, which is of crucial significance for the development of photonic devices that can be used for a long term. In view of this, the research and development of advanced multifunctional photonics devices (e.g., detector, photonic diode, switcher, sensors, and modulator) based on GDY is not only of great significance to fully understand the optical performance of all-carbon nanomaterials, but also promotes the development of photonic devices based on 2D materials.Ultrafast lasers which can be passively generated using saturable absorption of 2D materials play a pivotal role in various cutting-edge technologies such as micromachining, [26] hyperfine medical surgery, [27] and ultrafast information processing. [28] However, up to now, most of the ultrashort pulse generation Graphdiyne (GDY) is a novel 2D all-carbon nanomaterial, which has an intransic band gap, strong light-matter interaction, and large optical absorption in the infrared region, indicating that it has great potential in the field of mid-infrared ultrafast photonics. Here, a Z-scan method is used to demonstrate the broadband and strong nonlinear optical (NLO) response of GDY, and its performance in the application of mid-infrared ultrafast photonics is explored for the first time. The experimental results demonstrate that its nonlinear parameters are superior to the current...

Broadband Nonlinear Photonics in Few‐Layer Borophene

“…2D materials have been proved that they can be served as an excellent saturable absorber (SA) in passively mode‐locked (PML) fiber lasers. [ 45–51 ] SA is an optical device whose optical absorption loss is inversely proportional to light intensities, and it plays a significant role in a laser system for ultrashort pulse generation. Therefore, it is desirable to investigate the potential application of the borophene‐based SA in ultrafast lasers.…”

Diethylamino‐fluorographene: A 2D material with broadband and efficient optical limiting performance (from 500 to 1800 nm) with very large nonlinear optical response

“…The NLO response and the optical limiting performance of CDEA dispersed in acetone were studied using the Z-scan technique. [39][40][41] This technique is a relatively simple, single-beam transmittance measurement technique, which allows for the simultaneous determination of the sign and the magnitude of the nonlinear refraction and absorption properties of a sample. In Z-scan, the sample is moving along the propagation direction (e.g., the z-axis) of a focused gaussian laser beam, experiencing different incident laser intensity at each position.…”

2D GeP-based photonic device for near-infrared and mid-infrared ultrafast photonics

“…In general, the mode locking in fiber lasers by employing the NLO absorption properties of 2D materials can be regarded as one of the most efficient approaches to achieve ultrashort pulse generation. Up to now, the ultrashort pulse fiber lasers based on 2D materials at near-IR band have been widely investigated, including 1.0-µm fiber lasers [14][15][16] and 1.55-µm fiber lasers [17,18]. In order to further promote the application and development of ultrashort pulses, it is greatly important to investigate the ultrashort pulse fiber lasers at mid-IR band.…”