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Objective Existing agents to induce enamel self-repair and inhibit the progression of dental caries in the early stage have been proven to be inadequate and far from satisfactory. In this study, a honokiol-loaded poly(amido amine) (PAMAM) dendrimer (PAMH) was constructed to combat early caries lesions in enamel. Methods PAMH was prepared via a codissolution method. Computational simulation analysis was used to explore the mechanism of honokiol release. The cytotoxicity of PAMH was tested. The antibacterial effects of PAMH were tested by planktonic growth assays and biofilm formation inhibition assays. The remineralization effect of PAMH was examined via transverse microradiography and scanning electron microscopy after a pH cycling model. The in vivo anti-caries effect of PAMH was carried out in a rat model. Results Honokiol released from PAMH was slower but more durable in a cariogenic pH environment than in a neutral pH environment, which could be explained through the computational simulation analysis results. Under electrostatic action, P3 beads with the same charge repelled each other and extended outwards, resulting in the rapid expansion of the PAMAM dendrimer and accelerating the release of the drug. At a low pH of 5.5, the protonated P3 beads were not charged and the protonated P1 beads were positively charged. However, the electrostatic repulsive interaction between protonated P1 beads was restricted by the P3 beads in the outermost layer of the PAMAM dendrimer, so the swelling rate was relatively slow, resulting in the slow release of drug molecules in the acidic environment. The cytotoxicity demonstration and the biocompatibility experiment in animal study showed that PAMH is biologically safe. PAMH showed excellent enamel remineralizing ability after pH cycling and showed a long-term antibacterial effect in vitro. Meanwhile, PAMH showed long-term anticaries efficacy in vivo. Significance Our findings indicated that PAMH had great potential to combat early caries lesions in enamel for future clinical application.

Large mode area (LMA) fibers are widely used in high power fiber lasers to solve the nonlinear problems. In this work, a Nd3+-doped phosphate glass LMA fiber with heterogeneous helical claddings (HHC) is fabricated successfully by rod in tube method for the first time. The performance of the preform glass was matched well and suitable for drawing the fiber, and the related fabrication method is helpful for other special structure fiber fabrication. The fiber performance such as loss and gain coefficients are both tested and compared respectively. The experiment results show that the loss coefficient α will increase with the decrease of Λ (helix pitch) or r (fiber core radius), furtherly, the net gain coefficient g will become larger with the increase of r or Λ. The experiment results are beneficial to the HHC fiber design furtherly. As the HHC fiber has an all-solid-state structure, it is easy to fabricate relatively and convenient for cutting, splicing, etc. Thus, the HHC fiber will have potential applications in the field of fiber lasers.

The ridge waveguide on the TGG crystal has been fabricated through the combination of the ion implantation and the femtosecond laser ablation. Firstly, optical planar waveguide was formed on the to...

Melt processing is a promising process to fabricate Mg–CNTs (carbon nanotubes) composites with high performance and large dimensions. In this work, the liquid-mixing technique and ball-milling processes as well as the stirring casting method were used to prepare ZM1-1.0CNTs-L and ZM1-1.0CNTs-B composites, respectively. The composites were studied using optical microscopy (OM), Raman spectroscopy, scanning electron microscope (SEM), transmission electron microscope (TEM) and room-temperature tensile test. The results show that the yield strength (YS), ultimate tensile strength (UTS), elongation and microhardness values of the ZM1-1.0CNTs-L composite are improved by 37.3%, 29.6%, 37.0% and 33.3%, respectively, compared with those of ZM1 alloy. The uniform dispersion of CNTs as well as the strong interfacial bonds with the Mg matrix is the main reason for the significant improvement in mechanical properties of the as-cast composite. Liquid mixing combined with the stirring casting method is favorable to fabricate Mg–CNTs composite with high mechanical properties.

The work reports on the preparation and optical characterization of 75P2O5-15B2O3-9Al2O3-Bi2O3 glass by using the melt-quenching method and absorption spectroscopy, respectively. Further, 0.4-MeV proton implantation of a fluence of 8.0 × 1016 ions/cm2 was carried out on this glassy sample and it was tested as a waveguide at a wavelength of 632.8 nm for the first time to our knowledge. The m-line curves of the waveguide were measured before and after successive annealing treatments. The formation theory of the planar waveguides is discussed through simulations of the energy loss distribution and analysis of the reconstructed refractive index profile. The results should be useful in the design and fabrication of bismuth-doped phosphate glass and its use in integrated photonics devices.

In this work, we report the fabrication of an optical waveguide by single-energy H+ ion implantation in the Er3+-doped phosphate glass. The ion implantation conditions are with energy of 0.4 MeV and a fluence of 8.0×1016 ions/cm2. The dark mode spectrum of the waveguide structure was measured by the prism coupling experiment. The refractive index change along with the penetration depth was fitted by using the reflectivity calculation method (RCM). Finally, the calculated near-field light intensity distribution shows superior waveguide properties, which demonstrates its promising potentials for compact optical integrated devices.

The optical planar waveguides were fabricated by proton implantation with an energy of 400 keV and a dose of 8 × 1016 ions / cm2 or 400-keV helium-ion implantation with a fluence of 6 × 1016 ions / cm2 in the fluoride lead silicate glass. The morphologies were studied by a Zeiss microscope to estimate the thickness of the waveguides. The annealing effects on the fluoride lead silicate glass waveguides were investigated by 60 min annealing cycles at different temperatures ranging from 260°C to 310°C in air atmosphere. The dark-mode spectra and corresponding effective refractive indices before and after the thermal treatments were measured by the prism coupling system. The Stopping and Range of Ions in Matter 2013 code was used to simulate the irradiation process and calculate the energy losses. The refractive index distributions were reconstructed by the reflectivity calculation method. The near-field light intensity profiles of the proton and helium-ion implanted fluoride lead silicate glass waveguides were measured by the end-face coupling system. The comparison of optical properties between the proton-implanted waveguide and helium-ion implanted one was carried out. The experimental results show that the helium-ion implantation is more suitable for the fabrication of the fluoride lead silicate glass optical waveguides and the He + -implanted waveguide has better optical propagation performances.

Constructing the glass matrix to avoid the concentration quenching is significant to obtain heavily doping and higher optical gain glasses. In this work, B2O3-Na2O binary glasses with different O/B were employed for discussing the relationship between the glass structure and erbium ions concentration quenching. The Raman spectra indicated that when the O/B was 0.16, the [BO3] would be mostly transformed into [BO4] in the glass network, and furtherly increased O/B, the [BO3] would not be transformed into [BO4] continuously. The critical doping concentration was highest when the O/B was 0.16, which suggested that the relative complete framework structure would be beneficial to obtain homogenously distribution of rare earth ions. Lower O/B, more diverse of the glass structure units, which would be favor to obtain broadband width of NIR fluorescence of Er3+ ions.

Graphene nanosheets (GNS) are the promising nano-reinforcements to fabricate bulk graphene-metal composites due to their excellent mechanical properties and large yield. However, the effective synthesis of such bulk graphene reinforced magnesium (Mg) composites remains challenging because of the poor interfacial bonding and the aggregation of GNS. Here, GNS possessing about 12 at. % residual oxygen (∼7:1 C/O ratio) was synthesized by a thermal reduction method. These residual oxygen in GNS is beneficial to increase the interfacial bonding between GNS and the matrix of α-Mg by MgO nanoparticles, which synthesized through the occurrence of a reaction between the residual oxygen and α-Mg in the composites. TEM analysis reveals that the in-situ synthesized MgO nanoparticles can significantly improve the interfacial bonding between GNS and α-Mg owing to the formation of semi-coherent interface of MgO/α-Mg and the distortion area bonding interface of GNS/MgO. By filling 0.5 wt. % of GNS, the yield strength and elongation of the composite increased by 76.2% and 24.3%, respectively as compared to the matrix alloy. The significant improvement in mechanical properties of the composites is mainly due to the grain refinement, strong interfacial bonding and dislocation strengthening.

As a kind of inorganic luminescent material, the glasses doped rare earth ions have presented significant application in the field of white-light lighting and display. Herein, we successfully prepared a new kind of phosphate glass co-doped Tm2O3 and Dy2O3. In the case of a certain Dy2O3 concentration, the bulk densities of phosphate glasses increased with increase in Tm2O3 concentrations, while the variation in molar volume was opposite. As for the optical absorption spectra, seven absorption peaks can be clearly found in the range of 300 nm to 750 nm, based on the absorption spectra, the calculated J-O parameters followed the tendency of Ω2 > Ω6 > Ω4. Besides, four emission peaks were evidently found under 350 nm light excitation, which were located at 454, 484, 575, and 665 nm, respectively. As the working temperature was about 150°C, its photoluminescence intensity can still maintain 81.39% of the initial photoluminescence intensity. Meanwhile, the fluorescence lifetimes of glasses gradually decreased with the increasing of Tm2O3 concentrations, and the date of CIE coordinates and CCTs were recorded to confirm that the glass doped 0.4 mol.% Tm2O3 exhibited excellent comprehensive properties, such as suitable chromaticity coordinates (0.3505, 0.3790), low CCT (∼ 4899K

Terbium scandium aluminum garnet crystal is a promising material which has excellent characteristics for magneto-optical devices. We report on the fabrication of optical planar and ridge waveguides in the terbium scandium aluminum garnet by using combination of helium ion implantation and precise diamond blade dicing. The conditions for the ion implantation are an energy of 400 keV and a fluence of 6 × 1016 ions/cm2. The rotating velocity and cutting speed of the diamond blade were set to be 20,000 rpm and 0.1 mm/s, respectively. The implantation depth and distributions of energy loss were calculated by the stopping and range of ions in matter 2013. The refractive index distribution and the dark-mode spectrum for the implanted planar waveguide were obtained by the reflectivity calculation method and the prism coupling system, respectively. The near-field intensity profiles of both the planar and ridge waveguides were measured by the end-face coupling technique. The optical guiding properties of the terbium scandium aluminum garnet waveguides suggest that they can serve as candidates for optical waveguide isolators.

In this work, we report on the preparation and characterization of the planar and ridge optical waveguides in the E r 3 + -doped germanate glass by combining hydrogen ion implantation and precise diamond blade dicing. The nuclear energy loss and the implantation depth were calculated by the SRIM 2013 software. The refractive index profile was obtained by the reflectivity calculation method. The dark-mode spectrum and the near-field intensity distribution were measured by the prism coupling system and end-face coupling technique, respectively. This work has important reference significance for the development of E r 3 + -doped germanate glass active devices in the optical communication field.

Planar waveguides in magneto-optical glasses (tb3+-doped aluminum borosilicate glasses) have been produced by a 550-kev proton implantation at a dose of 4.0 x 10(16) ions/cm(2) for the first time to our knowledge. after annealing at 260 degrees c for 1.0 h, the dark-mode spectra and near-field intensity distributions are measured by the prism-coupling and end-face coupling methods. the damage profile, refractive index distribution and light propagation mode of the planar waveguide are numerically calculated by srim 2010, rcm and fd-bpm, respectively. the effects of implantation on the structural and optical properties are investigated by raman and absorption spectra. it suggests that the proton-implanted tb3+-doped aluminum borosilicate glass waveguide is a good candidate for a waveguide isolator in optical fiber communication and all-optical communication. (c) 2016 elsevier ltd. all rights reserved.

The work reports on a concise investigation on the application of the proton implantation and the femtosecond laser ablation for the infrared two-dimensional waveguide formation in the Nd3+-doped phosphate glass. The Nd3+-doped phosphate glass was firstly irradiated by the 400-keVprotons with a fluence of 8.0 × 1016 ions/cm2 and then ablated by the femtosecond laser with 800-nm central wavelength, 1.0-kHz repetition rate and 120-fs pulse duration. The optical microscope image of the end-face was captured by an optical microscope for the implanted and ablated Nd3+-doped phosphate glass. The intervals between two neighbor grooves was 30 μm. The guiding characteristics of the 2D waveguide were measured by the end-face coupling technique. The results suggest that a 2D waveguide operating at 976 nm is fabricated in the Nd3+-doped phosphate glass. The hybrid fabrication technique opens a versatile and flexible way toward 2D photonic devices in the Nd3+-doped phosphate glass.

Ion implantation and precise diamond blade dicing are amazing tools allowing the accurate formation of waveguide structures. In this work, we report on the fabrication and assessment of a ridge waveguide in the high-gain Nd3+-doped laser glass by the 400-keV H+-ion implantation with a fluence of 8.0 × 1016 ions/cm2 and the precise diamond blade dicing at a rotating speed of 2.0 × 104 rpm. The relative atom displacement induced by the proton implantation was simulated by the SRIM 2013. The cross section of the two-dimension structure was captured by a microscope and its lateral dimensions were 3.75 μm × 10 μm. The optical confinement of the ridge waveguide was recorded by the technique of the end-face coupling and its propagation loss was about 3.9 dB/cm at 976 nm. The ridge waveguide supported mono-mode at 976 nm can serve as a photonic device.

An optical waveguide is an important dielectric device that guides the propagation of light waves. Ion implantation is a competitive waveguide preparation technique with advantages including reliance, simpleness and flexibility. In this work, a 400-keV helium ion implantation with a fluence of [Formula: see text] ions/cm2 was carried out to manufacture a planar waveguide on the surface of the fused silica glass. The formation mechanism of the waveguide was analyzed by the nuclear energy deposition based on the SRIM 2013 and the refractive index distribution with the help of the reflectivity calculation method (RCM). The geometry structure and the guiding performance of the waveguide were studied by the metallographic microscope and the end-face coupling system, respectively. The investigation on the fabrication and characteristics of fused silica glass optical waveguides is of great significance for the development of passive devices in the field of optical communications.

The 400 keV proton implantation with a fluence of [Formula: see text] ions/cm2 was applied on the [Formula: see text] co-doped phosphate glass to fabricate a planar waveguide structure. The mode profile at the end face of the waveguide was measured by the end-face coupling technique. The energy loss profile of the energetic protons was calculated by the SRIM 2013. The refractive index distribution was simulated by the reflectivity calculation method. Based on these results, the formation theory of the planar waveguides was discussed through simulating the energy loss distribution and analyzing the reconstructed refractive index profile, which could be used for applications in the future integrated optical systems.

Gain guided and index alternate-guided (GGIA-G) fiber is suggested by our group recently. In order to grasp more laser performance of the GGIA-G fiber, the threshold characteristics of the fiber laser is analyzed in this work. Firstly, the improved rate equations of the forward pumped GGIA-G fiber laser are established and solved. Secondly, the threshold pump power of the GG-IG fiber, GG-IAG fiber and GGIA-G fiber are compared, and the effects of parameters including Nd3+ concentration N, fiber length L, fiber core radius a, refractive index difference Δn and output mirror reflectivity R2 on the threshold pump power Pth are discussed in detail, separately. Finally, the method of designing the fiber parameters for single mode laser operation is given out. When R1s=1.0, R2s =0.8, a=50 μm, N=1.0×1020 cm−3, L2: L=0.2 and Δn=-0.005, the allowed fiber length range for single mode laser operation is about 4.1 cm∼9.0 cm. The related research results will be helpful to the better application of the GGIA-G fiber.

To improve the mechanical properties of tellurite glass fiber, a hybrid-cladding optical fiber with Tm3+/Ho3+ co-doped TeO2-WO3-La2O3 glass core, tellurite glass inner cladding and phosphate glass outer cladding was proposed and fabricated by rod in tube and twice drawing method in this work. The spectroscopic characteristics of the core glass were systematically investigated too, the results showed that the maximum emission cross section was about 7.91 × 10−21 cm2, the longest fluorescence lifetime at 2030 nm was 2.47 ms, the value of σem × τrad was 19.53 × 10−21 cm2ms, and the maximum gain coefficient was about 2.02 cm−1 when 1.2 mol% Tm3+ and 0.6 mol% Ho3+ were co-doped in tellurite glass. The hybrid-cladding tellurite glass fiber fabrication process was presented in detail. A single-mode glass fiber with hybrid-cladding was fabricated and NA1 of the core is 0.116, and NA2 of the inner cladding is 1.249 and is beneficial for pump light collection. The core diameter of which is 6.8 μm, and the fiber loss is 20.16 dB/m. The fabricated hybrid cladding glass fibers can be easily cut without obvious defect.

As a kind of rare earth luminescent material, the development of white light-emitting glass cannot be ignored. Here, we successfully prepared series of Tm3+-Dy3+ co-doped P2O5-SrO-BaO-ZnO glasses. Structural analysis showed that the glass network is mainly composed of orthophosphate, pyrophosphate, and metaphosphate units. In the case of a certain content of Tm3+ or Dy3+, the densities of PSBZ glasses increased with the increasing of Dy3+ or Tm3+ content. From the optical absorption spectra, eight distinctive absorption bands can be found in the wavelength of 300 nm–750 nm. Under the excitation of 354 nm UV light, four main peaks corresponded to the transition of 1D2 → 3F4 and 4F9/2 → 6HJ (J = 15/2, 13/2 and 11/2) were found at 452 nm, 483 nm, 574 nm, and 663 nm, respectively. Besides, the CIE chromaticity coordinates, CCTs, and fluorescence decay curves were recorded to confirm the glass Tm0.4Dy1.0 showed excellent chromaticity coordinates (0.3392, 0.3334), suitable CCT (5188K) and relatively high fluorescence lifetime (434.68 μs) compared to other glasses prepared in this work, indicating that this glass has potential applications in WLED devices.

To clarify the relation between the concentration and ~3.4 μm emission of Er3+, a series of TeO2 based glasses with Er3+ concentration from 2.0 to 10.0 mol% were prepared by conventional melting-quenching method. The physical and spectroscopic characteristics of Er3+-doped tellurite glasses were systematically investigated. The Judd-Ofelt theory was used to analyze the absorption spectra. The emission intensity of ~2.7 μm and upconversion at 550 and 670 nm were discussed. The intensity increased when the Er3+ concentration increased to 6 mol%, and then drastically decreased with further increasing Er3+ concentration. The trend of the emission properties in NIR with the Er3+ concentration was also discussed. With increasing Er3+ concentration, the emission cross section at ~3.4 μm increased from 1.37 × 10−21 cm2 to 2.53 × 10−21 cm2. The results indicate that the highly doped Er3+ concentration may be an effective route to achieve efficient ~3.4 μm emission in Er3+ doped tellurite glasses.

The heterogeneous helical cladding (HHC) fiber is a new type of extreme large mode area fiber proposed by our group firstly. In this work, Nd 3 + -doped phosphate glass HHC fibers with different core radius r ( 60 μ m – 175 μ m ) and different helix pitch Λ (5.25 cm and 10.5 cm) were fabricated successfully. Firstly, the fiber preform glass was designed and prepared, and the performance of which was measured. Secondly, the HHC fiber preform was made by rod-in-tube method. Thirdly, the HHC fiber was obtained by the spiral drawing method, then the loss and gain performance of which were measured. Based on the experiment results, the following conclusions can be drawn: the larger the Λ (or r), the lower the loss coefficient L, and when r (or Λ ) is the same, the larger the Λ (or r), the higher the net gain coefficient. This work will facilitate the further exploration and application of the HHC fiber.

The k9 glass emerges as the promising host for the waveguide formation, owing to its unique optical properties. Ion implantation is a powerful technique for the fabrication of optical waveguides. In this work, the 400-keV proton implantation at a dose of [Formula: see text] [Formula: see text] was performed on the k9 glass to manufacture optical waveguide. Continuous annealing treatment at intervals of [Formula: see text] was used to enhance the guiding performances of the waveguide. The dark-mode spectrum and the refractive index profile of the waveguide were obtained by a prism coupling system and a reflectivity calculation method, respectively. The near-filed intensity distribution was measured by an end-face coupling equipment. The results suggest that the light field can be confined within the waveguide layer.

In this paper, the fabrication of optical planar waveguide in PTR glass by proton implantation is reported for the first time to our knowledge. The planar waveguide with a width of approximately 3.4 μm was generated under the condition of 400 keV H+ ion implantation with a dose of 8.0 × 1016 ions ‧ cm−2 at room temperature. The formation mechanism of PTR glass waveguide was illustrated with the aid of the SRIM program. The optical characteristics of the PTR waveguide, such as refractive index profile and near-field intensity distribution, were investigated in detail. The fabricated PTR waveguide presents a structure of both index-well and optical barrier according to the reconstructed refractive index profile. The finite-difference beam propagation method was carried out to simulate guiding modal distribution. Besides, in order to study the thermal stability of the H+-implanted PTR waveguide, annealing treatment was conducted at different temperatures.

Sm[Formula: see text]-doped bismuthate glass has been synthesized by means of the classic melt-quenching technique. Its optical properties were characterized, which included refractive index, absorption and fluorescence spectra. The measured data suggest that the Sm[Formula: see text]-doped bismuthate glass is suitable for optoelectronic applications. A Sm[Formula: see text]-doped bismuthate glass waveguide operating at 1.539 [Formula: see text]m has been manufactured by using the proton implantation with a 0.4 MeV energy and a 8.0 × 10[Formula: see text] ions⋅cm[Formula: see text] fluence for the first time to our knowledge. The effective refractive indices of the propagation modes for the glass waveguide were obtained by the m-line technique. The energy loss caused by the collision of the irradiated protons and the nuclei of the target Sm[Formula: see text]-doped bismuthate glass was calculated by the SRIM 2013. The refractive index profile and the near-field guided mode distribution for the waveguide structure were fitted through the reflectivity calculation method (RCM) and the FD-BPM method, respectively. The proton-implanted Sm[Formula: see text]-doped bismuthate glass waveguide is an alternative for an integrated device in the telecommunication band.

In this work, the high-gain Nd3+-doped laser glass was chosen as the target material, and the optical waveguide was formed on the glass by the H+ ion implantation under the conditions of a 8.0 × 1016-ions cm−2 fluence and a 0.4 MeV energy. The post-annealing at 200 °C for 1 h was applied to improve the optical quality of the waveguide. A metallographic microscope was used to detect changes in morphology caused by implanted ions in the high-gain Nd3+-doped laser glass. The characteristics of the ion-implanted high-gain Nd3+-doped laser glass optical waveguide, such as the dark-mode profiles and the near-field intensity distributions, were measured by experimental instruments including a prism coupler and an end-coupling system. The effects of nuclear energy loss of implanted ions on the refractive index variation of the substrate were analyzed by the reflectivity calculation method. The interaction mechanism of implanted protons with the high-gain Nd3+-doped laser glass was discussed by the SRIM 2013 code. It lays a theoretical and experimental basis for the development of high-gain Nd3+-doped glass waveguide lasers and amplifiers.

Nd3+:SrAlF5 nanocrystals embedded fluorophosphate glass–ceramics were prepared by the melt quenching and subsequent thermal treatment method. The formation of SrAlF5 nanocrystals in the glass was confirmed by X-ray diffraction and scanning electron microscope. The fluorescence intensity and lifetime of the glass–ceramics increased with the increase of size of nanocrystals. Importantly, by controlling growth of nanocrystals, an obvious enhancement of lifetime (725 μs) emerged in the glass–ceramics heat-treated at 510 °C and the transmittance can reach to 72.2 % at 1049 nm. The enhanced fluorescence intensity and lifetime were ascribed to the comfortable local environment to the Nd3+ ion and scattering of the nanoparticle embedded into the glass matrix.

Tb3+-doped aluminum borosilicate glasses are important magneto-optical materials for optical isolators. Optical waveguides are basic components in integrated photonics. By using the ion implantation technique, optical guiding structures can be produced in Tb3+-doped aluminum borosilicate glasses, and miniaturized waveguide isolators can be realized. In this paper, planar waveguides have been fabricated in Tb3+-doped aluminum borosilicate glasses by (6.0 + 5.5) MeV carbon ion implantation at doses of (8.0 + 4.0) × 1013 ions/cm2. The optical properties of optical waveguides are measured by equipments of prism coupling and end-face coupling systems. They are also analyzed by simulation programs of intensity calculation method and beam propagation method. The waveguides with good optical performances suggest potential applications on fabrication of waveguide isolators in Tb3+-doped aluminum borosilicate glasses.