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Newly long afterglow phosphor-in-glass (PiG) plays pivotal roles in the region of optical data storage. By using solid-phase reactions and unique spectrum modulation methods, a color-tunable PiG with decent persistent phosphorescence which can be tuned from green to blue has been fabricated. Lu3Al2Ga3O12: Ce3+, Cr3+ (LuAGG: Ce3+, Cr3+) based on TBZNA glass could emit bright green light signal located at 350 and 420 nm ascribed to the 5d1/5d2-4f transitions when corresponding optical data was being loadout. The doping of Cr3+ increases the density of the trap and provides additional traps between the shallow trap and the deep trap to capture more electrons, further improving afterglow decay time. And the storage time and cyclic reading times are derived by the method of thermal stimulation. Thereinto, tunable emission color has been obtained via changing the concentration of Ga3+, using UV excitation. Moreover, the influence of the Cr3+/Ga3+ on luminescence properties of long-afterglow-PiG materials have been described in detail. Achieved results confirm that it makes LuAGG-PiG as a long afterglow PiG matrix, demonstrating its promising application in optical data storage.

Er3+/Yb3+ co-doped Y2Ti2O7 (YTOEY) nanobelts with a thickness of ∼100 nm are synthesized by electrospinning, which exhibit a high sensitivity and rapid responsiveness in temperature sensing. The fluorescence intensity ratio of two green intense signals that originated from the transitions of Er3+ ions can be developed for non-contact temperature measurements. Moreover, the nanoscale dimensions, porous structures and large surface area of the prepared YTOEY nanobelts allow the photothermal signals to pass through them quickly. The maximum absolute sensitivity at 513 K and the extreme relative sensitivity at 303 K are calculated to be 0.37% K−1 and 1.17% K−1, respectively, indicating that the nanobelts have attractive optical temperature sensing characteristics. These extraordinary results demonstrate that YTOEY nanobelts are a promising candidate for accurate temperature monitoring in thermo-sensitive equipment.

The Eu3+ doped fluoride bi-layer ceramic/glass composite (GCZBL-Eu) was prepared by a one-step method and the effective wide visible-range fluorescence was recorded. The de-population rates of the 5D0, 5D1, 5D2, and 5D3 multi-levels in the glass layer (GZBL-Eu) were estimated to be 214, 746, 1163, and 680 s−1, respectively, and that in the ceramic layer (CZBL-Eu) were 211, 730, 1075, and 654 s−1, which implies multi-channel radiative transitions due to the non-radiative relaxation limitation of low OH content and low phonon energy. Simultaneously, the quantum efficiencies of the 5D0 levels in GZBL-Eu and CZBL-Eu were as high as 98.5% and 94.8%, respectively, thus demonstrating the effectiveness of the radiative transition emissions from Eu3+. Besides, GCZBL-Eu with the glass forming layer increases the emission intensity by 24% compared to CZBL-Eu, which is attributed to the multiple-cycle reflection in the composite structure of the glass–ceramic transition region, and the color coordinates of CZBL-Eu (0.483, 0.385) and GCZBL-Eu (0.469, 0.389) show that they can release yellowish-white light. The hetero-structured GCZBL-Eu provides a new approach for laser lighting, fluorescent display, and up-conversion applications.

Na(Y1−x−yHoxYby)F4/PAN (NYF-HY/PAN) composite fibers were synthesized using an electrospinning method, and the sub-micron crystals embedded in the fibers had complete hexagonal crystal structures. Under 977 nm laser excitation, strong green and red up-conversion (UC) emission that originated from flexible fibers were due to the radiative transitions (5F4, 5S2) → 5I8 and 5F5 → 5I8 of Ho3+, respectively. The effective green fluorescence emission (539 and 548 nm) can be applied to micro-domain non-contact temperature measurements, realizing rapid and dynamic temperature acquisition in a complex environment without destroying the temperature field. In the temperature range of 313–393 K, the absolute and relative sensitivity of the fibers are 0.00373 K−1 and 0.723% K−1, respectively, which indicates that the NYF-HY/PAN composite fibers have good thermal sensitivity. Composite fibers in which crystallites are embedded have superior properties, with great stability, high sensitivity, and excellent flexibility, providing a reliable reference for developing temperature-sensing materials for the biomedical field.

High-crystalline, hollow-mesh-like Tm3+/Yb3+-co-doped La2Ti2O7 (LTO) submicron fibers are prepared by electrospinning technique and identified as monoclinic structure. The LTO matrix fibers and the Tm3+/Yb3+-co-doped fibers exhibit different frequency upconversion luminescence. The fluorescence of the matrix at the 487 and 542 nm is ascribed to the two-photon absorption and the cross-relaxation processes caused by the defect center at 977 nm excitation, respectively. The upconversion luminescence intensity enhances when the rare-earth ions are incorporated into LTO fibers. The emissions of Tm3+ in co-doped LTO membranes at 479 and 789 nm under the excitation of 977 nm indicate the effectiveness of the three- and two-photon absorption processes, respectively. The pristine LTO fibers have the potential to be employed for water purification as a laser-excited photocatalytic material because the LTO materials are conducive to absorbing the highly penetrating NIR laser. Furthermore, the Tm3+/Yb3+ ions play a positive role in further promoting the laser-absorption capacity, and the hybrid excitation mechanism in the Tm3+/Yb3+-co-doped LTO composite fibers provides a new perspective for the development of anti-laser inorganic materials.

Adaptive fluoride ceramic with glass forming layer (GCZBL-Er) used in laser anti-escaping has been prepared by one-step synthesis, and the thickness of glass layer is identified as ~0.41 mm. Blue, green and red emissions of Er3+/Yb3+ codoped fluoride ceramic (CZBL-Er) and glass layer (GZBL-Er) have been investigated under ~980 nm laser pumping. With the forming of thin glass layer on ceramic surface, the absorption intensities on diffuse reflection of GCZBL-Er at 974 nm and 1.53 μm increase by 48% and 53% than those of CZBL-Er. Excited by a 979 nm laser, the presence of the glass layer increases the absolute absorption rate in spectral power from 75% in CZBL-Er to 83% in GCZBL-Er, which is consistent with the improvement in the absorbed photon number. In addition, the quantum yield of GCZBL-Er complex is raised by 28.4% compared to the case of ceramic substrate by photon quantification. Intense absorption-conversion ability and efficient macroscopical anti-escaping effect confirm the superiority of ingenious structure in the fluoride ceramics with glass forming layer, which provides a new approach for developing the absorption-conversion materials of anti-NIR laser detection.

Lithium niobate on insulator (LNOI) has already become a promising material platform for ultracompact, high‐performance, and low‐cost passive microphotonic devices. However, studies on an active LNOI platform are relatively slow. Current work aims at developing an important integrated photonic piece, an active LNOI thin film and waveguide. Herein, it is first demonstrated that a full wafer‐scale (3 in. in diameter) Er3+‐doped LNOI (Er:LNOI) wafer can be fabricated by directly ion‐beam slicing a commercially bulk Er3+‐doped lithium niobate wafer. Then, a number of rib‐type waveguides with a cross‐section

Radiation-level 1D2 adaptive fluorophosphate glasses (NBFP) have been exhibited and relevant transition emissions of Pr3+ have been quantitatively characterized. Intense visible fluorescence is proved to generate from 1D2 level principally and the quantum yield (QY) of emissions originating from this level is as high as 7.94% in 500–900 nm, indicating the decisive significance of the 1D2 level in reddish-orange fluorescence of NBFP glasses. Effective broadband 1.47 μm near-infrared (NIR) emission ascribed to 1D2→1G4 transition has been observed, meanwhile, the full-width at half-maximum is obtained to be 141 nm and the maximum stimulated emission cross-section is derived to be 5.75 × 10−21cm2, suggesting the effectiveness of the NIR emission from the initial level 1D2 in the specific NBFP glasses. In view of absolute radiation parameters and fluorescence branch ratios, net emission photon number of the attractive NIR emission is expected to be 4.5 × 1014cps under 453 nm laser pumping with 82.05 mW power, and corresponding QY is anticipated to be 2.0%. High shortwave transparency and moderate phonon energy are confirmed to be two important indicators for exploring suitable host materials in achieving effective radiations from 1D2 level of Pr3+, revealing the forward-looking applications of fluorophosphate glasses as broadband NIR amplifiers and irradiative luminescence sources.

Li2Gd4(MoO4)7: Eu3+/PMMA composite flakes (LGMP: Eu3+) have been obtained via embedding Eu3+-activated LGM polycrystalline precursor powders into polymethyl methacrylate (PMMA). The precursor powder with a size of ∼7 μm is confirmed to form the sea-island-like structure by SEM, which is helpful to the stability of the particle-polymer coexistence network in LGMP: Eu3+ flakes. Differential photon-generating behaviors are revealed under short-wave radiation and the effectiveness of PMMA is verified in reducing the mutual collision probability and avoiding the powder agglomeration. Although the LGMP: Eu3+ system has lower powder content in contrast to the pure precursor, its luminosity is still comparable to the pure one due to its favorable particle dispersibility. Efficient photon-conversion and intense red-emission indicate the organic-inorganic composite of PMMA loaded LGM: Eu3+ system is a potential candidate for solid-state lighting and color displays.

Tb(acac)3 (TAH) and Eu(TTA)3Phen (ETP) doped polyacrylonitriles (PAN) have been electrospun into heterogeneous hybrid TAH/ETP/PAN and core-shell structured [(TAH/PAN)core + (ETP/PAN)shell] wire-shaped flexible nanofibers with diameter of ∼350 nm. Differential photon releasing behaviors reveal the double-color-emitting potential of Tb3+/Eu3+ combination systems and verify the effectiveness of coaxial configuration in avoiding the cross-relaxation between different rare earth ions. Luminous fluxes of the hybrid and the coaxial systems exceed 283.5 and 326.3 μlm under the excitation of 308 nm UVB-LED pump source, respectively. By adopting coaxial electrospun configuration, the color coordinates are tuned from (0.561, 0.332) in TAH/ETP/PAN to (0.435, 0.366) in [(TAH/PAN)core + (ETP/PAN)shell] fibers, which demonstrates that the core-shell structure is promising to extend the dimension of color tuning. Nanofibrosis and electrospun configurations furnish a desired approach to develop multifunctional one-dimensional nanomaterials for color displays and optoelectronic sensors.

In this paper, we report the design and realization of 2-D focus scanning of the reflected beam by exploiting the frequency dispersion characteristic of reflectarrays operating at terahertz (THz) frequencies. In the first design, we choose four focal points on a circular path at four different frequencies ranging from 0.225 to 0.3 THz and 2-D beam scanning in the focal plane is achieved as frequency increases. To increase the scanning area, we design a dual-band reflectarray and 1-D scanning is achieved in each of the operating bands with different focal positions along the direction orthogonal to the scanning. The proposed reflectarrays are fabricated and their 2-D focus-scanning abilities are measured and there are good agreements between the simulation results and the measurements. The proposed designs demonstrate and expand further the potential applications of reflectarrays in fast THz imaging and detection.

Dy3+ doped multi-component tellurium-borate (MTB) glasses are identified to be an effective phosphor for laser-driven white illumination. Quantitative characterization of absolute spectrum parameter reveals that 2.0 wt% Dy2O3 doped MTB glass processes excellent quantum yield as high as 14.42%. The color parameters of white fluorescence are effectively emendated by adjusting the sample size and the pumping power when the preferred doping concentration is determined. The chromaticity parameters including luminous flux, color coordinate and correlated color temperature in 5.48 × 2.28 × 2.11 cm3 bulk glass phosphor are derived to 3.21 lm, (0.350, 0.331) and 4719 K closed to the pure-white fluorescence when the excitation power is enhanced to 252.7 mW. Effective white fluorescence depended on controllable photon distribution demonstrates that Dy3+ doped MTB glasses have promising application in developing laser-driven white light sources.

Under 980 nm wavelength excitation, 530 and 550 nm green upconversion emission spectra of erbium-doped gadolinium gallium garnet single-crystal were measured in the temperature range of 298–423 K for ratiometric thermometry based on fluorescence intensity ratio (FIR). The crystal shows strong emission intensity, highly efficient ratiometric thermometric performance, as well as thermally stable emission spectral structure, it is thus a promising luminescent material for ratiometric thermometry. A multiple ratiometric thermometry is proposed and demonstrated in comparison with the usually adopted ratiometric thermometry based on integrated emission intensity. The multiple ratiometric thermometry considers six FIRs involving two component peaks of the 530 nm emission band and three component peaks of the 550 nm emission band, which result from an electronic transition from one Stark sublevel of the 2H11/2 or 4S3/2 state to another of the ground state 4I15/2 of Er3+. All the six FIR schemes show highly efficient sensing performances with slightly different temperature characteristics. The temperature is overall determined by the six FIR schemes, largely increasing the reliability of temperature measurement.

Miscible-order fluoride-phosphate blocky phosphor (FBP), composed with ordered-phase of NaYF

We demonstrate efficient waveguide amplifiers based on erbium-doped lithium niobate on insulator with optical net gain of > 5 dB in a compact 5-mm-long waveguide at 1531.6 nm signal wavelength.

In recent years, surface-enhanced Raman scattering (SERS) of a molecule/metal–semiconductor hybrid system has attracted considerable interest and regarded as the synergetic contribution of the electromagnetic and chemical enhancements from the incorporation of noble metal into semiconductor nanomaterials. However, the underlying mechanism is still to be revealed in detail. Herein, we report an irreversible accumulated SERS behavior induced by near-infrared (NIR) light irradiating on a 4-mercaptobenzoic acid linked with silver and silver-doped titanium dioxide (4MBA/Ag/Ag-doped TiO2) hybrid system. With increasing irradiation time, the SERS intensity of 4MBA shows an irreversible exponential increase, and the Raman signal of the Ag/Ag-doped TiO2 substrate displays an exponential decrease. A microscopic understanding of the time-dependent SERS behavior is derived based on the microanalysis of the Ag/Ag-doped TiO2 nanostructure and the molecular dynamics, which is attributed to three factors: (1) higher crystallinity of Ag/Ag-doped TiO2 substrate; (2) photo-induced charge transfer; (3) charge-induced molecular reorientation., The authors report that near-infrared light induces an irreversible accumulated Surface-enhanced Raman scattering (SERS) behavior of a molecule/metal–semiconductor hybrid system. They investigate the underlying mechanism and show that it is attributed to crystallinity, charge transfer and reorientation.

The Eu

Multivariate terbium-complexes were incorporated into polyacrylonitrile (PAN) and electrospun into flexible multifunctional nanofibers with a uniform diameter of ~200 nm. Fluorescence comparison in multi-ligand-binding nanofibers under ultraviolet (UV) radiation verifies that the differentiated β-diketone ligands with dual functions are the primary cause of the spectral fluctuation, adequately illustrating the available methods for the quantification of intermolecular reciprocities between organic ligands and central Tb3+ ions. Especially under 308 nm UVB-LED pumping, the total emission spectral power of supramolecular Tb-complexes/PAN nanofibers are identified to be 2.88 µW and the total emission photon number reaches to 7.94 × 1012 cps which are nearly six times higher than those of the binary complex ones in the visible region, respectively. By modifying the sorts of organic ligands, the luminous flux and luminous efficacy of multi-ligand Tb-complexes/PAN nanofibers are up to 1553.42 μlm and 13.72 mlm/W, respectively. Efficient photon-releasing and intense green-emission demonstrate that the polymer-capped multi-component terbium-complexes fibers have potential prospects for making designable flexible optoelectronic devices.

This publisher’s note reports corrections to the text in Photon. Res. 9, 2319 (2021).PRHEIZ2327-912510.1364/PRJ.432906

Multi-photon-excited green, red and oxblood UC emissions have been quantified in highly transparent Ho3+/Yb3+ doped fluorotellurite (BALMT) glasses under the excitation of 977 nm laser. The net powers of green, red and oxblood emissions are determined to be 88.1, 103.8 and 66.1 μW in 0.196% Ho2O3 and 0.752% Yb2O3 co-doping case under the excitation power of 870 mW, and the net emission photon numbers are identified to be 242.7 × 1012, 342.8 × 1012 and 250.8 × 1012 cps. The quantum yields (QYs) and luminous fluxes for visible UC emissions of Ho3+ are identified as a positive dependency with pumping powers, and when the excitation power density increase to 110.8 W/mm2, the QY values for 550 nm green, 650 nm red and 753 nm oxblood UC emissions are up to 0.63 × 10−4, 0.90 × 10−4 and 0.65 × 10−4, respectively. The values of QY in Ho3+ doped BALMT glass are one order of magnitude larger than that in NMAG glasses. The macroscopic quantization for UC photon generation from Ho3+ in low-phonon fluorotellurite glasses provides a reliable reference for developing compact high-power-density illuminant for remote sensing, radar detection and medical diagnosis.

Eu(BA) (TTA)2/PVP and Eu(BA) (TTA)2Phen/PVP are electrospun into nano-spider-web-like fibers with diameters about 100–300 nm. Differential luminescence behaviors are revealed under ultraviolet (UV) radiation and effectiveness of Phen ligand is verified in enhancing red emission behavior. Total emission photon number and luminous efficacy are derived to be 7.96 × 1013cps and 9.91%lm/W in Eu(BA) (TTA)2Phen/PVP fiber, respectively, which are 1.4 times higher than those of Eu(BA) (TTA)2/PVP fiber under the excitation of 367 nm UVA light emitting diode (UVA-LED) pump source. Similar results on absolute spectral parameters of the tri-ligand fibers under the excitation of 308 nm UVB light emitting diode (UVB-LED) further support the availability of europium-complexes/PVP spider-web-like fibers for red-light therapy. Improved emission behavior and higher photon emission indicate that europium-complexes/PVP spider-web-like fibers can play a positive role in absorbable and curative medical sutures.

Under 980 nm wavelength excitation, green upconversion emission spectra of Er3+ ions in NaYF4 (NYF) micro-crystals were measured in the temperature range of 298–383 K. A multiple ratiometric thermometry is proposed to realize reliable temperature sensing. It considers six luminescence intensity ratios(LIRs) involving two peaks at 530 nm emission band and three peaks at 550 nm emission band, which concern electronic transitions between crystal-field Stark sublevels of Er3+. The six LIR schemes display similar temperature characteristics with high thermometric efficiency. The temperature can be overall determined by the six LIR schemes, largely increasing measurement reliability. The study also shows that the 980 nm excitation power adopted neither induces a detectable temperature change nor has a noticeable effect on the LIR value. In addition, the Er3+-doped NYF phosphor displays intense green emissions and thermally stable spectral structure which are desired for the multiple ratiometric thermometry.

Erbium(Er)/thulium(Tm)-codoped active lithium niobate(LiNbO3) channel waveguides were fabricated by titanium diffusion following erbium/thulium co-diffusion doping in an X-/Z-cut LiNbO3 substrate with an initial congruent/Li-deficient composition. We show that the waveguide is in an initial congruent or Li-deficient composition environment, remains LiNbO3 crystalline phase, is monomode at the 1.5 µm wavelength region under either the transverse electric or the transverse magnetic polarization, and has a loss

Efficient warm yellowish-white fluorescence emissions of Dy3+ were observed in heavy metal germanium tellurite (HGT) glasses under the excitation of 454 nm. Further, the luminescence intensity of Dy3+ is increased by ∼29% accompanying the introduction of Ag NPs with diameter ∼7 nm when compared with that of the silver-free case, which is caused by the existence of localized surface plasmon resonance (LSPR). The larger net emission power, the more net emission photon number and the higher quantum yield in Dy2O3 doped HGT glasses containing Ag NPs (HGT-Ag) confirm the availability of utilizing laser. Presupposed fluorescence color trace reveals that white luminescence can be achieved when the intensity ratio between residual laser and Dy3+ emission reaches the appropriate range. The productive transition emissions and the tunable white fluorescence illustrate tellurite glasses embodying noble-metal NPs are a potential candidate for high-quality lighting devices.

Titanium-diffused lithium tantalate (Ti:LT) multimode planar waveguide was produced by in-diffusion of titanium thin-film deposited onto a Z-cut congruent LT substrate. Titanium concentration (CTi) in the titanium-diffused layer was profiled by secondary-ion-mass-spectrometry. Modes guided in the waveguide were characterized by prism coupling technique. Refractive index in the waveguide is profiled on the basis of the measured mode indices, and is related to the CTi profile. The results show that both the refractive index and the CTi profiles obey to a Gaussian function. The profiles of titanium-induced extraordinary and ordinary index changes are almost identical, implying that the index change in the Ti:LT waveguide has a small anisotropy and the confinement to the mode field is polarization-insensitive. The ordinary and extraordinary index changes reveal a similar exponential dependence on the CTi with a power index of ∼0.8.

Excitation-power dependency of upconversion (UC) photons have been quantified in Tm3 +/Yb3 + doped fluorotellurite (BALMT) glasses under the excitation of 975 nm laser. The net powers of three-photon-excited blue and red and two-photon-excited NIR emissions are determined to be 242, 101 and 7994 μW in 0.5 wt% Tm2O3 and 2 wt% Yb2O3 co-doping case under the excitation power of 870 mW, respectively, and the net emission photon numbers are identified to be 58.2 × 1013, 33.0 × 1013 and 3253.2 × 1013cps. The quantum yields (QYs) for multi-photon-excited UC emissions of Tm3 + are identified as a positive dependency with pumping powers, and the relativity for three-photon fluorescence is extremely severe. When the excitation power density is set to 110.8 W/mm2, the QY values for 476 nm blue and 650 nm red UC emissions are up to 1.49 × 10− 4 and 0.84 × 10− 4, and furthermore, the value for 809 nm NIR UC emission is as high as 83.22 × 10− 4. The 809 nm luminescence is one of the good matching wavelengths for iris recognition in NIR ranges, the intensive NIR luminescence and the efficient blue fluorescence are promising in scanning and positioning for iris scanning. The macroscopic quantization for UC photon generation from Tm3 + in low-phonon fluorotellurite glasses provides a reliable reference for developing compact high-power-density light sources in iris recognition.

Ga3+-diffused lithium tantalate (LiTaO3) strip optical waveguide was fabricated by diffusion (at 950 °C for 1.5 h) of 8-μm wide, 112-nm thick Ga2O3-strips photolithographically patterned onto a Z-cut congruent LiTaO3 substrate. Crystalline phase, composition, optical properties and profile characteristics of Ga3+ ions in the waveguide were investigated. We show that the waveguide retains LiTaO3 crystalline phase and is in congruent composition environment. Optical studies show that the waveguide supports single-mode propagation (at the 1.5 μm wavelength) of not only the extraordinary wave but also the ordinary wave, shows considerable polarization dependence in mode field distribution, and has a loss of 0.2/0.4 dB/cm for the ordinary/extraordinary wave. Secondary ion mass spectrometry analysis shows that the Ga3+ profile follows a sum of two error functions (a Gaussian function) in the width (depth) direction of the waveguide.

Ti-diffused near-stoichiometric(NS) LiTaO 3 multimode planar waveguide was fabricated by diffusion of Ti-film coated onto a congruent LiTaO 3 substrate and post Li-rich vapor transport equilibration process. The crystalline phase in the Ti-diffused layer was analyzed by powder x-ray diffraction and the Li 2 O-content was evaluated from the measured birefringence. The Ti-concentration profile was analyzed by secondary ion mass spectrometry. The modes guided in the planar waveguide were characterized by prism-coupling technique. The refractive index profile was constructed from the measured mode indices, and correlated with the Ti-concentration profile. The results show that the waveguide retains the LiTaO 3 phase and is in an NS composition environment. Both the refractive index and Ti-concentration follow Gaussian profile. The extraordinary and ordinary index change profiles are almost same, implying that the electric field profile of the mode guided in the NS Ti:LiTaO 3 waveguide would be polarization-insensitive. The ordinary and extraordinary index changes and the Ti-concentration follow a similar exponential relationship with a power index ∼1.3. Comparison shows that the Ti:LiTaO 3 waveguide shows considerable differences from the Ti:LiNbO 3 in Ti diffusivity, index change profile and its relation to Ti-concentration, and polarization dependence of guided mode.

All-inorganic dual-phase CsPbBr3-Cs4PbBr6 quantum dots (CPB QDs)-based polyacrylonitrile (PAN) fiber synthesized by supersaturated recrystallization and electrospinning technique possesses characteristics of homogeneous morphology, high crystallinity and solution sensitivity. Under 365 nm laser excitation, CPB@PAN fiber exhibits surprising trace-recording capability attributing to the splash-enhanced fluorescence (FL) performance with a narrow-band emission at 477–515 nm. In the process of ethanol anhydrous (EA) and water splashing, the CPB@PAN fiber presents conspicuous blue and green emission when contacting with EA and water, and maintains intense blue and green FL for more than 4 months. These experimental and theoretical findings provide a facile technology for the development of biological protection display, biotic detection and moisture-proof forewarning based on the trace-recording performance of CPB@PAN fiber.

Phy-X/PSD was applied to evaluate the properties of gamma and neutron attenuation of TeO2–B2O3–RnO (R = Mg, K, and Zn) glass systems which is fabricated successfully by high temperature melting method. The abilities of gamma ray shielding were investigated by the relative parameters effective atomic number (Zeff), half-value layer (HVL), tenth value layer (TVL), mean free path (MFP), and fast neutrons (ΣR) which are crucial gamma shielding parameters. Meanwhile, the parameter of ΣR plays an essential role for evaluating the abilities of the neutron shielding. The study results revealed a phenomenon that the improving of TeO2 fraction from 11 mol% to 61 mol% decreases the parameters of gamma shielding μ, μ/ρ, Zeff, and ΣR, and also increases HVL, TVL, and MFP parameters, which based on the high atomic number of tellurium. Furthermore, the prepared glasses were effective shielding material which can reduce fast neutrons as well as gamma rays, illustrating that prepared glass system possesses excellent properties of gamma shielding.

Miscible-order NaGdF4 fluoride-phosphate phosphor has been synthesized based on tin-fluorophosphate glass with low-melting-point, retaining excellent luminescence property of fluoride nanoparticles. Multi-peak emissions from metastable 5DJ (J = 0, 1, 2 and 3) levels are released effectively in the Eu3+ doped fluoride nanoparticles, which lifetimes are at the order of millisecond and quantum efficiency at 5D0 level in high Eu3+ concentration still remains 88.9%. On the basis of multi-peak emissions from Eu3+ and wide-band blue framework from Sn2+, the color coordinates of the fluoride-phosphate phosphors are regulated to the white light region and the color rendering index reaches up to 88. Tunable color and high color rendering index make fluoride-phosphate phosphor become a potential candidate for high-quality white light source.

We developed a highly efficient optical thermometer based on intensity ratio of upconversion green fluorescence of Er3+/Yb3+-codoped NaYF4 microcrystals. The sensor consists simply of a 980nm laser diode, one narrow-band interference filter, two lenses, one Si-photocell and one multimeter, while being without use of spectrometer and additional electronics. The device not only has a simple, compact structure (hence a low cost), but also displays highly efficient sensing performance, characterized by large signal-to-noise ratio due to strong fluorescence intensity, high thermal resolution and sensitivity, which have the values 1.3K and 1.24×10-2K-1, respectively, at the physiological temperature 310K. The excellent sensing performance of the device was further confirmed by the results of the measurements repeated using a spectrometer. The thermometer is highly generalized that can be applied to other luminescent materials, and shows great potential for the physiological temperature sensing in biological tissues and cells.

Temperature characteristics of 980-nm-upconverted green 530 and 550 nm fluorescence of Er3+-doped SrGdGa3O7 single crystal have been studied for temperature sensing purposes. To achieve that, a simple experimental setup has been developed that consists of a 980 nm laser diode, two interference filters, two Si-photocells and two multimeters, while without use of monochromator or focusing lens for fluorescence collection. The study shows that the Er3+-doped SrGdGa3O7 crystal displays strong green emission intensity (hence good signal-to-noise ratio) and high temperature sensitivity of fluorescence intensity ratio of the 530 and 550 nm emissions, which is (5.6–104.0) × 10−3 K−1 in the considered temperature range 100–430 K, depending on the temperature. In addition, the experiments were repeated using a spectrometer and consistent results of temperature characteristics were obtained. Present study shows that the Er3+-doped SrGdGa3O7 crystal is a promising host material for optical temperature sensing.

Dy3+ doped fluoroborate (NCZLB) glass phosphors were designed and fabricated, and efficient photon releasing confirms the effectiveness of laser pumping. Quantitative characterization reveals that net emission powers and net emission photon numbers of 1.00 wt% Dy2O3 doped NCZLB glass were identified to be 618.9 μW and 17.2 × 1014cps under the excitation of 453 nm laser with 15.81 mW power, respectively, and the quantum yield was solved to be 25.9%. Potential fluorescence color trace was presupposed by change of intensity ratio between residual laser and Dy3+ emission, and pure white luminescence are expected when the intensity ratio reaches the appropriate range. Optimizing of size and doping concentration for the Dy3+-doped NCZLB glass phosphor achieves anticipated white lighting effect under blue laser excitation, and the luminous flux is up to 9.07lm. Effective white fluorescence depended on controllable photon releasing demonstrates that the Dy3+ doped NCZLB glasses have promising application as laser-driven white light sources for solid-state illumination.

Polarization rotator-splitters (PRSs) are crucial components for controlling the polarization states of light in classical and quantum communication systems. We design and experimentally demonstrate a broadband PRS based on the lithium niobate on insulator (LNOI) platform. Both the rotator and splitter sections are based on adiabatically tapered waveguide structures, and the whole device only requires a single etching step. We show efficient PRS operation over an experimentally measured bandwidth of 130 nm at telecom wavelengths, potentially as wide as 500 nm according to simulation prediction, with relatively low polarization crosstalks of ∼ − 10 dB . Our PRS is highly compatible with the design constraints and fabrication processes of common LNOI photonic devices, and it could become an important element in future LNOI photonic integrated circuits.

BaYF5: Eu3+-fluorophosphate (BYF: E-FP) miscible-phase phosphors with tunable white fluorescence and high color-rendering index (CRI) are synthesized by blending Ba(Y1−xEux)F5 (BYF: E) submicron crystals (SCs) into fluorophosphate glass. Adjusting the concentration of Eu3+ purposefully, the comparable intensity of blue, green and red components by multichannel emissions can be regulated to achieve the adjustable white light. The quantum efficiency of 5D0 level in Eu3+ reaches up to 90.8%, and the millisecond fluorescence lifetime of blue and green emissions from 5D1, 5D2 and 5D3 levels exhibit the effectiveness of metastable levels. In coordination with blue emission from Sn2+, the color coordinates of BYF: E-FP are concentrated in white region of chromaticity diagram and its CRI is able to reach as high as 86. Tunable white fluorescence and high CRI indicate that miscible-phase phosphors possess promising applications in optoelectronic lighting.

(Ba1−x−yErxYby)MgF4/PAN (BMF-EY/PAN) fibers have been prepared by electrospinning technique, in which composite fibers vested with smooth surface, excellent flexibility and self-calibration temperature sensing function. Under 977 nm laser excitation, the strong green and red up-conversion (UC) emissions produced by the flexible fibers through effective UC luminescence are considered to be a two-photon absorption process, attributing to 2H11/2/4S3/2 → 4I15/2 and 4F9/2 (Ⅰ)/4F9/2 (Ⅱ) → 4I15/2 radiation transitions of Er3+, respectively. Combined utilization of green (523 and 545 nm) and red (656 and 669 nm) emissions endows the composite fibers with the potential in microdomain temperature sensing, realizing the accurate temperature acquisition in complex environment. At a relatively moderate working temperature (363 K), the absolute (SA) and relative (SR) sensitivity values in fibers based on green-emission reach up to 0.351 and 0.824 %K−1 for main sensing, and correspondingly, the values depended on red-emission are 0.342 and 0.302 %K−1 for auxiliary sensing, respectively. Composite fibers inlaid with crystallites have superior performances in luminescence, thermal feedback and flexibility, providing a breakthrough for the development of temperature-sensing materials in biomedical field.