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Ti3C2Tx materials have been developed to have application space in many fields, but there are not many works that can be compatible with infrared (IR) stealth and electromagnetic interference (EMI) shielding at the same time. To realize the multiband high EMI shielding of Ti3C2Tx materials, and to achieve stealth effect in the IR band, in this work, a composite textile is prepared by combining the Ti3C2Tx material with a carbon cloth and sputtering a very thin gold film on the surface. This composite textile can realize high EMI shielding compatible with IR stealth, in which the EMI shielding efficiency for microwave Xa‐band (8GHza‐12.4GHz) is up to 71.8 dB, for microwave Kaa‐band (26.5GHza‐40GHz) is up to 75.02 dB, and for terahertza‐band is about 30 dB. IR emissivity is as low as 0.1, and the lowest emissivity under a certain temperature reaches 0.07, which can withstand a high temperature of 500 °C. In addition, this composite textile has flexible and bendable wear. The thickness of the whole textile is about 400 µm, of which the Ti3C2Tx material thickness is only about 10 µm, the thinnest reaches 2 µm. Such a textile can be used in both people's livelihood and military applications, which has far‐reaching significance. [ABSTRACT FROM AUTHOR]

Noise‐like pulses (NLPs) are becoming increasingly attractive for a variety of applications such as supercontinuum generation, materials processing, and low‐coherence spectral interferometry. Related research in the near‐infrared region is extensive, yet few studies have been reported in the mid‐infrared (MIR) region. Herein, a systematic investigation of MIR NLPs is made for the first time. An approach is presented by exploiting a polarization‐maintaining fluoride fiber in the mode‐locked oscillator to cause a polarization‐dependent delay between the orthogonal‐polarized components of intracavity circulating pulses, thus generating a series of ultrashort pulses which will eventually form a stable wave packet, namely, NLP. Numerical simulations based on the extended coupled nonlinear Schrödinger equations predict the generation of NLPs, and reveal key aspects of the pulse evolution. Experiments yield linearly polarized NLPs at 2.8 μm with a maximum average power of 498 mW and a spike width of 4.3 ps, corresponding to a pulse energy of 12 nJ. The experimental results are in good agreement with the simulation results. This work constitutes a major step toward the development of MIR ultrafast fiber lasers with NLPs output. [ABSTRACT FROM AUTHOR]

Plasmonic nanolasers as a new class of coherent laser beyond the diffraction limit have attracted a lot of attention. However, the ultrahigh optical confinement caused by the plasmon effect is inevitably accompanied by metal absorption loss, thus increasing the pump threshold of the plasmonic nanolaser. In the past decade, many good results about low threshold plasmonic nanolasers have been realized and successfully extended to various applications. Here, this advance is discussed and some opinions are offered. First, based on the theoretical model and key parameters of the plasmonic nanolaser, the factors affecting the threshold are analyzed. Subsequently, the experimental efforts on the realization of low threshold plasmonic nanolasers from optical pumping to electrical pumping are reviewed. Their applications in on‐chip optical interconnects, biochemical analysis, and far‐field structure are then considered. Finally, feasible approaches to threshold reduction are discussed, as well as more possible applications in the future. [ABSTRACT FROM AUTHOR]

Due to the low photon energy in the relevant frequency band, fewer materials can directly excite carriers, and an extreme lack of high‐performance, large‐area detectors, limit the promotion, and development of 6G technology. In addition, flexible detectors with the integration of 6G communication and Internet of Things technology has good prospects for application in the development of optoelectronic devices, which are also urgently needed. A large‐area flexible thin layer terahertz detector is designed that combines the advantages of excellent optoelectronic performance in the detection of electromagnetic waves with low photon energy and the localized surface plasmon (LSP) effect in a sub‐wavelength structure detector. Due to the large effective area, the spiral electrode device demonstrates the best performance at room temperature. The noise equivalent power (NEP) and photoresponsivity (RV) are achieved with 0.4 pW Hz−1/2 and 154 MV W−1 at 0.28 THz. In addition, the bending experiments show that the device has extreme advantages for flexible 6G detector applications. [ABSTRACT FROM AUTHOR]

Artificial optoelectronic synapses with flexibly regulated synaptic weight are crucial to the rapidly evolved artificial visual system. Although three‐terminal devices with transistor geometry have exhibited controllable synaptic response through applying electrical pulses on the gate terminal, the complicated device structure limits its integration with array configurations. In this work, a simple two‐terminal optoelectronic synapses array based on the ZnO/Al2O3/CdS heterojunction with tunable synaptic weight is presented. It can respond to UV and green light stimulation in a neuromorphic manner, allowing the implementation of the basic synaptic function. By introducing the piezo‐phototronic effect, the synaptic weight can be regulated in multilevels, extending the forgetting time by 30.08% and reducing training epochs for image recognition by 36.13%. In addition, the device can extract the target image from massive noisy optical inputs avoiding redundant data memorization. This work provides a novel method to regulate the synaptic weight of the simple two‐terminal device configuration through the piezo‐phototronic effect, showing potential applications for the mimicry of the human visual‐perception system. [ABSTRACT FROM AUTHOR]

Due to the slowdown of Moore's law, the integrated photonic devices have provided a route to promote the development of large‐scale optical communications with high performance. As one of the essential components of optical routers, an optical switch can fast transmit or block the optical signal. However, most of the integrated optical switches reported to date rely on thermo‐, magneto‐, or electro‐optical effects, which limit applications due to slow response times, large footprint, and complexity fabrication. Here, an integrated nonlinear optical switch designed by the inverse‐design method and fabricated on the SiN platform is introduced. The integrated optical switch is demonstrated with significant intensity‐dependent transmission at 1.5 µm waveband. The polarization‐depended capability is explored by using fundamental polarized lights (transverse electric and transverse magnetic, respectively), which exhibits opposite transmission change trends during the whole power range and opens potential applications such as photonic quantum information processing. In order to address the saturation of Kerr‐nonlinearity in SiN materials at high power, a MoS2/SiN hybrid integrated optical switch is fabricated by uniformly cladding few‐layer MoS2 on the surface of inverse‐designed region. That is demonstrated to enhance the nonlinear optical response of device efficiently and achieve more excellent switching capability at high power. [ABSTRACT FROM AUTHOR]

Using 3D sonic crystals as acoustic higher‐order topological insulators (HOTIs), 2D surface states described by spin‐1 Dirac equations at the interfaces between the two sonic crystals with distinct topology but the same crystalline symmetry are discovered. It is found that the Dirac mass can be tuned by the geometry of the two sonic crystals. The sign reversal of the Dirac mass reveals a surface topological transition where the surface states exhibit zero refractive index behavior. When the surface states are gapped, 1D hinge states emerge due to the topology of the gapped surface states. The zero refractive index behavior and the emergent topological hinge states are confirmed experimentally. This study reveals a multidimensional Wannier orbital control that leads to extraordinary properties of surface states and unveils an interesting topological mechanism for the control of surface waves. [ABSTRACT FROM AUTHOR]

Integrated photonics are expected to replace the conventional free‐space optical systems, yet there remains a challenge of low nonlinear response due to small nonlinear refractive index and short interaction length. Here, the large‐area monolayer MoS2 is used to facilitate excellent nonlinear response, and a pump strategy is proposed with respect to the spontaneous four‐wave mixing in the visible spectral range. The external pump incident from the top resonates in the GaN microdisk resonator and is thoroughly absorbed by the monolayer MoS2 to generate the four‐wave mixing pump via the excitonic photoluminescence. Being driven by the internal photoluminescence pump and enhanced by the microcavity structure, it is validated that the proposed structure well suffices efficient degenerate spontaneous four‐wave mixing generation. Since the emission spectrum can be tailored through careful temperature control, this work holds a great potential in various functionalities, not only on‐chip visible light sources but also optical field control. [ABSTRACT FROM AUTHOR]

Inorganic semiconductor arrays revolutionize many areas of electronics, optoelectronics with the properties of multifunctionality and large‐scale integration. Metal halide perovskites are emerging as candidates for next‐generation optoelectronic devices due to their excellent optoelectronic properties, ease of processing, and compatibility with flexible substrates. To date, a series of patterning technologies have been applied to perovskites to realize array configurations and nano/microstructured surfaces to further improve device performances. Herein, various construction methods for perovskite crystal or thin film arrays are summarized. The optoelectronic applications of the perovskite arrays are also discussed, in particular, for photodetectors, light‐emitting diodes, lasers, and nanogratings. [ABSTRACT FROM AUTHOR]

High‐power all‐fiber thulium lasers have gained considerable interest in recent times due to their distinct characteristics and versatile applications in the medical and industrial sectors. This review article presents a comprehensive examination of the advancements and challenges in this field. It begins with an overview of thulium‐doped silica fiber, which is a critical component for high‐power lasers operating at the 2 µm (micrometer) wavelength band. The research progress of essential high‐power thulium laser sources, including continuous‐wave (CW), quasi‐continuous wave (QCW), and pulsed lasers, is then thoroughly analyzed, highlighting their respective strengths and limitations. Additionally, the diverse applications of high‐power thulium fiber lasers in medical and industrial domains are summarized. Furthermore, the article emphasizes the current challenges in the advancement of high‐power thulium‐doped fiber lasers (TDFLs) and outlines potential avenues for future development. Despite TDFLs being the predominant laser source in lithotripsy and material processing applications, optimizing their performance and expediting further progress in thulium laser technology remain crucial objectives. This review article aims to provide valuable insights for researchers, engineers, and professionals working in the field of high‐power fiber lasers operating at 2 µm. [ABSTRACT FROM AUTHOR]

Group IVB transition metal dichalcogenides (TMDs) have attracted significant interests in photoelectronics due to their predictable superior physical properties compared to group VIB (Mo and W) TMDs. However, the nonlinear optical properties and ultrafast photonic devices based on group IVB TMDs remained unexplored so far. Herein, the nonlinear optical absorption of HfS2 nanosheets (NSs) prepared by liquid exfoliation is demonstrated. The usage of HfS2 as a new ultrafast photonic device for high‐energy and ultrashort pulse generation in a fiber laser is reported for the first time. A photonic crystal fiber (PCF) assisted deposition method is presented for the fabrication of an HfS2‐microfiber integrated saturable absorber (SA) device with precisely controllable light–matter interaction, which can benefit the output of the device. The HfS2‐microfiber SA device shows modulation depth of 15.7% and exhibits outstanding ultrashort pulse generation performance with pulse duration of 221.7 fs in the communication band. The experimental results suggest that HfS2 presents highly nonlinear optical absorption and can be developed into an excellent candidate of SA devices for the development of HfS2‐based ultrafast photonics. The nonlinear optical absorption of HfS2 nanosheets is demonstrated. Based on this nonlinear optical property, an HfS2‐based ultrafast photonic device is fabricated by integrating HfS2 with a microfiber. The usage of HfS2 for a new function of nonlinear optical materials in the generation of high‐energy and ultrashort pulses by fiber laser is reported. [ABSTRACT FROM AUTHOR]