Xiangeng Meng

Qilu University of Technology · Department of Materials Science and Engineering

Room temperature phosphorescence (RTP) has emerged as an interesting but rare phenomenon with multiple potential applications in anti‐counterfeiting, optoelectronic devices, and biosensing. Nevertheless, the pursuit of ultralong lifetimes of RTP under visible light excitation presents a significant challenge. Here, new phosphorescent materials that...

Organic multicolor heterostructures with spatially resolved luminescent colors and identifiable patterns have exhibited considerable potential for achieving micro-/nanoscale photonic barcodes. Nevertheless, such types of barcodes reported thus far are exclusively based on a single heterostructure with limited coding elements. Here, a directional se...

Quasi‐2D lead halide perovskites have garnered increasing interest as lasing gain media. Relatively simple fabrication, high refractive index, and unique quantum well structure encourage their use in traditional cavity lasers and cavity‐free systems called random lasers (RLs). Despite tremendous advances reported thus far, coherent random lasing in...

Electroluminescence efficiencies and stabilities of quasi-two-dimensional halide perovskites are restricted by the formation of multiple-quantum-well structures with broad and uncontrollable phase distributions. Here, we report a ligand design strategy to substantially suppress diffusion-limited phase disproportionation, thereby enabling better pha...

Developing solid‐state luminescent materials with bright long‐wavelength emissions is of considerable practical importance in light‐emitting diodes (LEDs) but remains a formidable challenge. Here, a novel structure engineering strategy is reported to realize solid‐state fluorescence (FL)‐emitted carbon dots (CDs) from visible to near‐infrared regio...

Fe3O4 is a promising anode material for high-power rechargeable lithium-ion batteries (LIBs) benefiting from its high reversible capacity, rich natural resources, and easy preparation. However, the rate capability and the cyclability of the Fe3O4 electrode are still unsatisfactory limited by its poor electronic conductivity and tremendous volume va...

Random lasing in organic-inorganic lead halide quasi-2D perovskite was observed by measuring lasing threshold, spectral narrowing, spectral correlations and critical volume. The photon transport mean free path is found to be comparable to the lasing wavelength, suggesting a hybrid localized-diffusive lasing regime.

Phase transformation between metal halide perovskites serves as a promising route to create new optoelectronic functionalities. Nevertheless, the transformation reported thus far mainly involves the transition between two individual phases (e.g., 0D-3D and 3D-2D), while the transition from one phase to a heterostructure with distinct phases has bee...

Cobalt sulfide-based electrode materials were believed to have bright future in lithium-ion batteries (LIBs) application for their high theoretical capacity and excellent electrochemical stability. However, their relatively low electronic conductivity and the large volume variation during lithiation/delithiation processes usually result in low rate...

Lanthanide-based metal–organic frameworks (Ln-MOFs) multicolor heterostructures have shown great potential for achieving anti-counterfeit applications. In their Research Article (DOI: 10.1002/anie.202109336), Zhenhua Gao, Xiangeng Meng, Yong Sheng Zhao et al. have developed a strategy to construct 2D lateral Ln-MOFs heterostructures. The domain-con...

Mehrfarbige Heterostrukturen auf der Basis von Lanthanoid-basierten metallorganischen Gerüsten (Ln-MOFs) haben großes Potenzial für fälschungssichere Anwendungen gezeigt. In ihrem Forschungsartikel (DOI: 10.1002/ange.202109336) präsentieren Zhenhua Gao, Xiangeng Meng, Yong Sheng Zhao et al. eine Strategie, um laterale 2D-Ln-MOFs zu konstruieren. Mi...

Dimension-tunable lateral Ln-MOFs heterostructures were realized through spatial semi-confinement induced steric hindrance. They exhibit domain-controlled emissive colors and identifiable dimensional-tunable lengths, offering unique opportunities to design integrated microstructures and smart devices toward advanced anti-counterfeiting applications...

Metal‐organic frameworks (MOFs) heterostructures with domain‐controlled emissive colors have shown great potential for achieving high‐throughput sensing, anti‐counterfeit and information security. Here, a strategy based on steric‐hindrance effect is proposed to construct lateral lanthanide‐MOFs (Ln‐MOFs) epitaxial heterostructures, where the channe...

Multicolor carbon dots‐based materials offer a variety of opportunities for potential applications in bioimaging, optoelectronic devices, and information security. In article number 2100421, Zifei Wang and co‐workers present a strategy for the first time based on thermally driven amorphous‐crystalline phase transition to achieve multicolor carboniz...

Optical multiplexing based on luminescent materials with tunable lifetimes holds potential applications in information storage and security. However, most of these materials reported so far are still limited to the microsecond level, which restrains their further applications. Herein, four kinds of green room-temperature phosphorescent (RTP) carbon...

Multicolor carbon dot (CD)‐based nanomaterials offer a variety of opportunities for potential applications in bioimaging, optoelectronic devices, and information security. However, it still remains a challenge to modulate the conjugated π‐structure of CDs to achieve multicolor room‐temperature phosphorescence (RTP). Herein, the authors present a st...

Room-temperature phosphorescent (RTP) carbon dots offer unique opportunities in information security applications, but the delay time of such materials reported thus far is typically shorter than 10 s and thus affects readout of the encoded information. Herein, a fast processable and one-step synthetic approach is developed for the preparation of N...

CsPbBr3 has been recognized as one of the most important members in the family of metal halide perovskites, which could offer high optical gain for low-threshold lasing. Despite of significant advances achieved thus far, it is still in high demand to develop new material platforms to further rationally design perovskite-based resonators. Here, CsPb...

Amorphous spherically‐shaped metal‐organic framework (MOF) microcavities have been constructed by amorphizing MOFs with a topological distortion network through introducing flexible building blocks, which possess a Q factor as high as ≈10⁴ and can provide sufficient feedback for high‐quality single‐mode lasing oscillations. The results will pave an...

Metal‐organic frameworks (MOFs) have recently emerged as appealing platforms to construct microlasers owing to their compelling characters combining the excellent stability of inorganic materials and processable characters of organic materials. However, MOF microstructures developed thus far are generally composed of multiple edge boundaries due to...

Zero-dimensional perovskites exhibit exotic optoelectronic responses, but stimulated emissions from such media remain elusive and challenging thus far. Here, we demonstrate for the first time the capability of zero-dimensional perovskite Cs4PbBr6 open systems to trigger low-threshold single- and two-photon pumped mirrorless lasing entitled "random...

Control of lasing properties through tailorable and dynamically tunable materials and reconfigurable compositions can augment the performance of random lasers for a wide range of applications. Here, a colloid of randomly dispersed weakly scattering single-layer titanium carbide (Ti3C2Tx) MXene flakes embedded within rhodamine 101 gain medium is exp...

An antisolvent approach is developed to fabricate phase pure zero-dimensional perovskite Cs4PbBr6 microrods at sub-millimeter length scales with the microrod length facilely controllable by the growth time. A strong greenish photoluminescence narrow band is observed in the developed Cs4PbBr6 microrods. The corresponding photoluminescence quantum yi...

Spatially responsive photonic barcodes have been designed based on spatially resolved responsive multicolor Ln‐MOF heterostructures, which facilitate an efficient authentication and exhibit great potential in fulfilling advanced anti‐counterfeiting. These results offer a comprehensive understanding of the function‐oriented construction of responsiv...

Micro/nanoscale photonic barcodes based on multicolor luminescent segmented heterojunctions hold potential for applications in information security. However, such multicolor heterojunctions reported thus far are exclusively based on static luminescent signals, thus restricting their application in advanced confidential information protection. Repor...

Rational design of bifunctional oxygen catalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) with high efficiency and low-cost are significantly in the development of rechargeable Zn-air batteries (ZABs). Herein, it is designed one-dimensional rod-like Mn3O4/NiCo2S4 nanostructure. The inner Mn3O4 nanorod and the outer co...

The rational design of high-performance tri-functional electrocatalysts plays an important role for the fast development of Zn-air batteries (ZABs) and water splitting and still remains a great challenge up to date. Herein, Co4N nanoparticles encapsulated in nitrogen doped carbon (Co4[email protected]) composite has been conveniently fabricated whi...

Photonic media containing hybrid noble metal–dielectric nanocrystals (NCs) represent a wonderland of nanophotonics, with a myriad of uncharted optical functions yet to be explored. Capitalizing on the unique phase separation and spontaneous formation of Au-metal NCs in a gallosilicate glass, we fabricated Ni2+-doped transparent nanoglass composites...

We propose a strategy to construct dynamically tunable random lasers by continuously adjusting the excited state of gain molecules spatially confined in nanoporous channels of metal-organic framework particles. Wavelength-tunable random lasers are achieved by thermally manipulating the intramolecular charge transfer process of gain molecules. The w...

Introducing of impurity ions into semiconductor nanocrystals can improve their photoluminescence quantum efficiency through energy transfer and enhance their applicability towards light-emitting devices. In this work, Mn doped CsPbCl3 and CsPbCl3-xBrx perovskite nanocrystals were prepared in glass through melt-quenching and subsequent thermal treat...

Fe3O4 has broad development aspect as an anode material for rechargeable lithium ion batteries due to its high specific capacity and low cost. The intrinsic low electrical conductivity and huge volume variation during cycle processes still hinder its practicability. Herein, we have explored a novel hierarchical porous Fe3O4@N-doped carbon (HP–Fe3O4...

Fluorescent carbon dots (CDs) have emerged as promising materials for white light-emitting diodes (WLEDs) on account of carbon's intrinsic merits of high stability, low cost, and environment-friendliness. However, CDs usually give relatively narrow emission with full width at half maximum within 70–90 nm, which fundamentally restrains construction...

Fluorescent carbon dots (CDs) are compelling optical emitters to construct white light‐emitting diodes (WLEDs). However, it remains a challenge to achieve large‐scale and highly efficient single‐component white‐light‐emissive CDs suitable for WLED applications. Herein, a low cost, fast processable, environmentally friendly, and one‐step synthetic a...

In this work, we have investigated the influence of La³⁺ and Y³⁺ doping on the spatial homogeneity of Ho³⁺ ions in high silica glasses via structural and spectroscopic analyses. It is found that both of La³⁺ and Y³⁺ doping could lead to depolymerization of the glass network. Under the same doping concentration, Y³⁺ gives rise to a larger silicate c...

Owing to quantum confinement of optical and electrical transitions within isolated [PbBr6]4- octahedral units, zero-dimensional perovskite Cs4PbBr6 exhibits appealing molecular-like quantum optoelectronic behavior. Although much effort has been made thus far, the origin of the visible photoluminescence observed in Cs4PbBr6 still remains unclear. In...

Glass materials have found various applications owing to their low cost, free of grain boundaries and open topological network to accommodate various active species. We have fabricated a ternary glass of Al2O3-MoO3-TeO2 (AlMoTe) and investigated potential applications in lithium-ion batteries (LIBs). we have found that the incorporation of a certai...

We report on a high-temperature vapor drop-casting technique used to fabricate a chemically stable nanomaterial‒CsPbBr3 quantum dot nanoglass that exhibits stable photoluminescence and stimulated emission properties. Such nanomaterial is comprised of two material domains: nano-fractured glassy-phase matrix and embedded CsPbBr3 quantum dots. The nan...

The substitution effect of 5 mol% calcium at perovskite B site was investigated systematically for yttrium doped barium zirconate, including phase structure, stability in different atmospheres, electrical conductivities and sinterability. In XRD patterns, BaZr0.8Y0.15Ca0.05O3-δ (BZYC5) powders synthesized by a citrate-nitrate combustion method show...

Early on, we had reported the preparation process of Ni‐BaZr0.1Ce0.7Y0.2O3−δ asymmetric cermet membrane (Ni‐BZCY ACM). In this work, we further optimized the sintering procedure and investigated the effect of water vapor in feed gas, operating time, H2 concentration difference across the membrane, and dense layer thickness of Ni‐BZCY ACM on hydroge...

A novel NiCo2O4/N-doped carbon nanowebs serving as a bifunctional electrocatalyst, consisting of hollow NiCo2O4 nanospheres and N-doped carbon nanowebs are prepared through a liquid-phase synthesis method accompanied by subsequent heat treatment. The N-doped carbon nanowebs mainly contribute to the high activity for oxygen reduction reaction, where...

Porous core–shell CuCo2S4 nanospheres that exhibit a large specific surface area, sufficient inner space, and a nanoporous shell were synthesized through a facile solvothermal method. The diameter of the core–shell CuCo2S4 nanospheres is approximately 800 nm„ the radius of the core is about 265 nm and the thickness of the shell are approximately 45...

A systematic approach to investigate lasing and net amplification in plasmonic structures with a finite‐difference time‐domain method coupled to the rate equations of four‐level and six‐level atomic systems is developed. The experiment‐fitted kinetic parameters are fed into the model to study the mechanism of the coupling of metamaterials and metas...

A series of Ce³⁺, Dy³⁺ doped Ca3(P1-xBxO4)2 phosphors were synthesized by a high temperature solid-state reaction method, and their corresponding structure, morphology, and luminescence properties were investigated. It is found that the crystal phase transition from β-Ca3(PO4)2 to Ca5(PO4)3(OH) gradually occurs with increasing the boron content in...

The Pr³⁺ doped oxyfluoride silicate glasses prepared by melt-quenching method are investigated. It is found that the replacement of CaO with Na2O in glass composition favors the formation of CaF2 crystals during the melt quenching process. The addition of Al2O3 and ZnO into glass composition enhances the ³P0 → ³H4 emission of Pr³⁺ ions. The self-ex...

MXenes are a recently discovered family of two-dimensional nanomaterials formed of transition metal carbides and carbon nitrides with the general chemical form Mn+1XnTx, where ‘M’ is a transitional metal, ‘X’ is either C or N, and ‘T’ represents a surface functional group (O, -OH or -F). MXenes are derived from layered ternary carbides and nitrides...

FeS2 nanosheets encapsulated in 3D porous carbon spheres (FeS2@C-2h) were fabricated by a series of treatment using Fe2O3 hollow nanospheres as start materials. We firstly fabricated the Fe2O3@PPy by a facile process in solution. Then, the Fe2O3@PPy was converted to the Fe3O4@C by annealing treatment under Ar atmosphere. Fe3O4@C composites etched i...

Random lasing with coherent feedback has been achieved in an ultrabroad spectral range of 533-870 nm when employing robust platforms based on amorphous media to provide optical feedback and modulating the gain curve. The pump threshold of the resultant random lasing is comparable to those reported with strongly scattering centers in crystalline for...

Nd³⁺-doped sol-gel silica glasses with enhanced spectroscopic properties via co-doped Al2O3 and La2O3 are reported. Co-doped Al2O3 and La2O3 not only significantly increases the fluorescence intensity and prolongs the fluorescence lifetimes of Nd³⁺, but also has a large σems × τf of the Nd-doped sol-gel silica glasses. The Judd–Ofelt parameters wer...

Cost‐effective ceramic tubes based on low‐price commercial calcined bauxite for economical separation were fabricated by a new phase‐inversion casting method. The thermal shrinkage and weight loss during heating of the green tubes were characterized by dilatometric analysis and TG, respectively. Three shrinkage stages appear successively, correspon...

The Dy and Eu activated Ca3B2O6 phosphors were synthesized by a high temperature solid state reaction technique and their structural and luminescent properties were investigated. The phosphors are characterized by X‐ray diffraction, photoluminescence spectra, and Commission International de I'Eclairage (CIE) chromaticity coordinates. It is found th...

Nanoporous CuO/Cu composites with a continuous channel structure were fabricated through a corroding Cu-Al alloy process. The width of the continuous channels was about 20~50 nm. Nanoporous structure could effectively sustain the volume expansion during the Na⁺ insertion/extraction process and shorten the Na⁺ diffusion length as well, which thus he...

In this work, Mn-doped MoS2 hierarchical nanotubes have been prepared by a solvothermol method. The diameter of Mn-MoS2 nanotubes is about 100~200 nm and the wall thickness is about 10~20 nm. Hierarchical ultrathin sheets are formed on the surface of MoS2 nanotubes. The formation mechanism of Mn-MoS2 nanotubes is discussed on the basis of contrast...

We explore the applications of MXenes, a new material class of growing interest, in the area of nanophotonics and plasmonics. A broadband plasmonic metamaterial absorber and a random laser device have thus been demonstrated.

Owing to exotic optical responses, metallic nanoparticles and nanostructures are finding broad applications in laser science, leading to numerous design variations of plasmonic nanolasers. Nowadays, two of the most intriguing plasmonic nanolasing devices are spasers and random lasers. While a spaser is based on a single metallic nanoparticle resona...

CoFe2O4 and NiFe2O4 nanoporous spheres were fabricated through a facile solvothermal method followed by post-thermal treatment and their potential applications in lithium-ion batteries were explored in this work. The obtained nanoporous spheres, assembled from a large amount of secondary small particles, have a uniform size distribution with diamet...

Hyperbolic metamaterials are anisotropic media that behave as metals or as dielectrics depending on light polarization. These plasmonic materials constitute a versatile platform for promoting both spontaneous and stimulated emission for a broad range of emitter wavelengths. We analyze experimental realizations of a single–photon source and of a pla...

In article number 1601031, Alberto Naldoni, Vladimir M. Shalaev, and co-workers present plasmonic titanium nitride (TiN) nanoparticles on top of TiO2 nanowires, which strongly improve the activity toward photoelectrochemical water splitting. Plasmonic TiN provides efficient generation of hot electrons due to a broadband absorption and improved elec...

Transition metal nitrides exhibit plasmonic properties in the visible and near infrared region and offer exceptional thermal, chemical, and mechanical stability. In article number 1600717, Vladimir M. Shalaev, Alexandra Boltasseva, and co-workers demonstrate a path to fabricate large-scale nanoarchitectures of plasmonic titanium nitride via nitrida...

The use of hot electrons generated from the decay of surface plasmons is a novel concept that promises to increase the conversion yield in solar energy technologies. Titanium nitride (TiN) is an emerging plasmonic material that offers compatibility with complementary metal-oxide-semiconductor (CMOS) technology, corrosion resistance, as well as mech...

Plasmonic titanium nitride nanostructures are obtained via nitridation of titanium dioxide. Results show that complex nano- and microscale designs of refractory plasmonic nitrides can be realized by utilizing the well-understood oxide material synthesis. Large-scale 3D nanoarchitectures will enable the use of refractory plasmonic materials in a var...

We present an approach employing a random metamaterial constructed by dispersing monolayer Ti3C2 nanoflakes into the gain medium for achieving random lasing. The optical feedback is suggested to be provided by Ti3C2 nanoflakes through saturable absorption.

Coherent nanoscale photon sources are of paramount importance to achieving all-optical communication. Several nanolasers smaller than the diffraction limit have been theoretically proposed and experimentally demonstrated using plasmonic cavities to confine optical fields. Such compact cavities exhibit large Purcell factors, thereby enhancing sponta...

Plasmonics, a technique to tightly concentrate light down to the nanoscaleby coupling photons to surface plasmons,has been employed to downscalelasersto sub-wavelength dimensions. The resultant device is called a spaser, short for surface plasmon amplification by stimulated emission of radiation, or more generally plasmonic nanolaser, which is bein...

The use of hot electrons generated from the decay of surface plasmons is a new paradigm to increase the conversion yield in solar energy technologies. Titanium nitride (TiN) is an emerging plasmonic ceramic that offers compatibility with CMOS technology, corrosion resistance, as well as mechanical strength and durability thus outperforming noble me...

Plasmonics has brought revolutionary advances to laser science by enabling deeply sub-wavelength nanolasers through surface plasmon amplification. However, the impact of plasmonics on other promising laser systems has so far remained elusive. Here, we present a class of random lasers enabled by three-dimensional plasmonic nanorod metamaterials. Whi...

The field of nanophotonics has experienced a dramatic development in recent years, which requires ample candidate structures to achieve desirable functionalities. For many novel device designs in emerging field of transformation optics, optical metamaterials, and others, non-uniform and non-conformal thin films as well as three-dimensional (3D) str...

We study lasing in two gold nanorod arrays, one exhibiting hyperbolic dispersion while the other is elliptic at the emission wavelength of Rhodamine 101. Results show the hyperbolic metamaterial provides stronger emission with reduced threshold.

A laser oscillation assisted by localized surface plasmons of nanostructured metals is described. A random laser is readily achieved in media where metallic nanoparticles are randomly dispersed. Surprisingly, laser oscillation is feasible even in such a medium where the scattering mean free path is as long as 200 mm, indicating that plasmon-enhance...

To study the light-matter interaction between plasmonic systems and gain media, numerous theoretical and numerical methods have been proposed. Among them, because of its accurate treatment of the quantum property of gain media, the time domain (TD) multi-physics approach is viewed as the most powerful method, especially for analysis of transient dy...

We developed an accurate three dimensional time domain model of a 4-level gain system fitted to lasing experiment with a silver nanohole array. The simulated emission intensity showed clear lasing effects confirmed by optical experiments.

We present a plasmonic approach employing a slanted silver nanorod array for achieving controllable random lasing in a strongly scattering regime. Such random lasers can serve as a bright optical source for speckle-free imaging.

The spaser offers an opportunity to achieve coherent optical sources at nanometer scales due to the extreme confinement of optical fields. However, achievement of spasers with directional propagation in the visible wavelength region remains a challenge thus far, owing to the unique optical feedback mechanism and large dissipative losses of the meta...

We demonstrate directional plasmonic nanolaser emission using subwavelength hole arrays perforated in metal film as plasmonic nanocavities. The lasing exhibits a single mode in the red wavelength region.

We report on novel light–emitting properties from monodispersed mesoporous silica particles embedded with β–Ga2O3 nanocrystals that were fabricated through a chemical approach followed by thermal annealing in specific atmosphere. The emission spectrum of such nanocomposites consists of several sharp peaks where the dominant one regularly shifts wit...

A SPASER, short for surface plasmon amplification by stimulated emission of radiation, is key to accessing coherent optical fields at the nanoscale. Nevertheless, the realization of a SPASER in the visible range still remains a great challenge because of strong dissipative losses. Here, we demonstrate that room-temperature SPASER emission can be ac...

Random lasing properties of dye solutions suspended with gold–silica core–shell nanoparticles are investigated. The core–shell architecture allows adjustment of plasmon coupling strength between metal and optical gain media by varying the thickness of dielectric shell. Consequently, multiple aspects of random lasers can be controlled, such as mode...

Random lasing properties of dye solutions suspended with gold–silica core–shell nanoparticles are investigated. The core–shell architecture allows adjustment of plasmon coupling strength between metal and optical gain media by varying the thickness of dielectric shell. Consequently, multiple aspects of random lasers can be controlled, such as mode...

We propose a plasmonic laser with uni-directional power outflow based on a symmetry broken core-shell nanoparticle. A detailed study of the emission mechanism of the sub-wavelength, directional light source is provided.

We report on two types of optical properties enhanced by surface plasmons of metal nanoparticles. One of them is wavelength-selective enhancement of birefringence in ZnO thin films with anisotropic microstructure in which Ag nanoparticles are dispersed. The other is random laser oscillation and amplified spontaneous emission in Au core-SiO2 shell n...

The spaser, a quantum amplifier of surface plasmons by stimulated emission of radiation, is recognized as a coherent light source capable of confining optical fields at subwavelength scale. The control over the directionality of spasing has not been addressed so far, especially for a single-particle spasing nanocavity where optical feedback is sole...

Supplementary Information for Unidirectional Spaser in Symmetry-Broken Plasmonic Core-Shell Nanocavity

A synthesis procedure of gold-silica core-shell nanoparticles has been developed in this work. We have investigated the effects of the amounts of poly(vinylpyrrolidone) (PVP), water, and tetraethoxysilane (TEOS) in the starting materials on the shell thickness. The results reveal that the modification of the surface of gold nanoparticles with PVP p...

We experimentally demonstrate the capability of tailoring lasing resonance properties by manipulating the coupling between surface plasmons and photons in random lasing media composed of metallic-dielectric core-shell nanoparticles and organic dyes. It is revealed that core-shell nanoparticle-based systems exhibit optical feedback features distinct...

We have systematically investigated random lasing properties in weakly scattering systems composed of a macroporous silica disk immersed in a dye solution where the solvent is a mixture of two alcohols. Controlling the refractive index of the mixed solvent allows us to vary the scattering strength over a wide range. We have found two different scat...

Metal nanoparticles are efficient scatterers for light at around the frequency of localized surface plasmon resonance. By randomly dispersing such strong scatterers in a gain material, a laser system is achieved. Multiple scattering leads to an optical feedback that selects lasing modes. This type of laser is called random laser and has been develo...

A viscoplastic finite element method for simulating powder sintering processes was presented. This method was formulated on the basis of the plasticity theory of a porous material to take the change in apparent volume during the sintering into consideration. To simulate non-uniform shrinkage in the sintering, the shrinkage strainrate was included i...

We report on the observations of coherent random lasers in weakly scattering polymer films embedded with silver nanoparticles. The dominant oscillation cavity calculated from the ensemble-averaged power Fourier transform spectrum of single-shot emission spectra is shorter by more than two orders of magnitude than the scattering mean-free path, indi...

Random lasers with coherent feedback have been obtained in highly transparent polymer films embedded with silver (Ag) nanoparticles. The hybrid materials were fabricated via in situ synthesis, through which Ag nanoparticles were precipitated by heat treatment. Sharp peaks with linewidth of ∼0.3 nm emerge on a broad emission background when the pump...

A series of d(0) ions, i.e., Ti4+, Zr4+, Nb5+, Ta5+, Mo6+, and W6+, has been incorporated into silicate glass matrix by utilizing a conventional melt-quenching method, and their optical properties have been examined. When the resultant glasses are excited by ultraviolet light, intense emissions are observed in the blue to orange wavelength regions...

We report on observations of random lasers with coherent feedback in highly transparent polymer films embedded with silver nanoparticles. The hybrid materials were fabricated via in situ synthesis method, through which silver nanoparticles were precipitated by thermal treatment. Sharp peaks with linewidth ~0.5 nm were observed to emerge on the broa...