Doping Concentration Of Er3 Research Articles

Anti-thermal quenching and temperature sensing properties of Er3+/Yb3+ co-doped Sc2O3 phosphors

Up-conversion luminescence from rare earth doped phosphor is a potential candidate as non-contact temperature sensor. In this work, different Er3+ concentration doped Sc2O3: Er3+/Yb3+ phosphors were prepared through typical sol–gel method. The emission intensity reached the maximum as the doping concentration of Er3+ was 1.0 mol%. While, different from high concentration (0.5, 1.0 and 2.0) of Er3+ doped samples, an abnormal enhancement in the two green emissions and red emission in Sc2O3: 0.3 mol% Er3+/ 2 mol% Yb3+ phosphors was observed through elevate temperature and the enhancement factor reaches 1.3 as the temperature changed from 303 to 513 K. The reason for this concentration dependent thermal enhancement could be interpreted by the competition between increased energy transfer and non-radiative transition. The temperature sensing properties of samples, including relatively sensitivity, temperature resolution and repeatability were investigated and the maximum values reached 1.03 × 10−2 K−1 (303 K), 0.524 K (303 K) and 99.65 % (303––513 K), respectively, in Sc2O3: 1 mol% Er3+/2 mol% Yb3+ phosphors. The results imply that they have good temperature sensing ability and can be used as an optical temperature probe in research and production.

Novel multi-mode anti-counterfeiting encryption material of CaAl12O19:Eu, Er with multi-color down-conversion luminescence, up-conversion luminescence, dynamic luminescence, and photochromism

Multi-mode dynamic anti-counterfeiting materials can provide complex anti-counterfeiting performance and ensure the anti-counterfeiting strategy becomes more secure. Herein, a new type of multi-mode anti-counterfeiting encryption material of CaAl12O19:Eu, Er with different Er doping concentration was developed by sol–gel method. Interestingly, the CaAl12O19:Eu, Er phosphor and its composite have multi-mode anti-counterfeiting characteristics of multi-color down-conversion luminescence, up-conversion luminescence, dynamic luminescence, and photochromism. Effect of different Er doping concentration on the down-conversion luminescence, up-conversion luminescence, dynamic luminescence, and photochromism of CaAl12O19:Eu, Er was systematically investigated, and the relevant mechanisms were discussed. These anti-counterfeiting features can be simultaneously applied in both bright and dark fields, which can achieve high-level anti-counterfeiting in both spatial and temporal dimensions. The CaAl12O19:Eu, Er phosphors cannot be easily replaced by other materials with the same anti-counterfeiting properties. They display good application foreground in the field of anti-counterfeiting encryption.

Bimolybdate single crystals codoping with trivalent ytterbium and erbium ions for high-stable and high-sensitive optical thermometry

Replacing conventional powder polycrystalline materials with crystalline materials is an effective strategy to improve the sensing sensitivity, responsiveness, and anti-interference capabilities of the fluorescence intensity ratio (FIR) based optical temperature sensing techniques. In this work, Yb3+/Er3+ codoped bimolybdate single crystals, NaBi(MoO4)2 (NBM) with different Er3+ ion doping concentrations, were grown by the Czochralski method, in which is expected to be used for optical temperature sensing applications. The structure of the crystals was fully characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, and transmission electron microscopy (TEM). Under 980 nm laser excitation, the crystals demonstrated notable green and slight red upconversion (UC) emissions, and the mechanism of UC luminescence was thoroughly investigated. The luminescence intensity was found to be contingent upon the doping concentration, which gradually decayed with increase of Er3+ ions. The optical temperature sensing performance of Yb3+/Er3+ codoped NBM single crystals was evaluated by the FIR technique based on the thermally coupled level of Er3+ ions (2H11/2/4S3/2). The experimental findings revealed that the 10 at% Yb3+, 10 at% Er3+: NBM crystal exhibited highest sensor sensitivity among the synthesized crystals, with a maximum absolute sensitivity of approximately 1.22 % K−1 at 510 K. Furthermore, the temperature sensing characteristics of the crystals appeared to be dependent on the doping concentration of Er3+ ions. In summary, the Yb3+/Er3+ codoped NBM single crystal showcased excellent sensor sensitivity and held considerable promise as materials for optical temperature sensing applications.

Growth, Spectroscopy, and Laser Performance of a 2.79 μm Er: YSGG Single Crystal Fibers.

Single crystal fibers combine the great specific surface area of fibers and the single crystal property of the bulk crystal which shows great potential for a high-power laser. For an Er-doped crystal, due to the fluorescence quenching at the 3 μm wavelength, high Er doping is necessary to increase the fluorescent up-conversion for the breaking limitation. However, a high Er doping concentration must lead to high heat accumulation, resulting in poor laser performance. Compared with an Er-doped bulk crystal, Er-doped SCF has the great potential to remove the heat in the crystal, and it is easy to obtain a high power. In this paper, Er: Y3Sc2Ga3O12 (Er: YSGG) single crystals were successfully grown using the micro-pulling-down method (μ-PD). Owing to the stably grown interface, the diameter of the crystal is 2 mm with a length up to 80 mm. Then, the measurements of Laue spots and Er3+ distribution indicated that our crystals have a high quality. Based on the as-prepared Er: YSGG SCF, the continuous-wave (CW) laser operations at 2794 nm were realized. The maximum output was 166 mW with a slope efficiency of up to 10.99%. These results show that Er: YSGG SCF is a suitable material for future high-power 3 μm laser operation.

Defects and self-trapped exciton regulation in rare-earth doped all-inorganic perovskites

By controlling the growth temperature and increasing Er-doping concentration in CsPbCl3xBr3(1−x):Er, their emitted PL can be tuned from red (1.82 eV) to near-infrared (1.53 eV) while keeping their intrinsic bandgap without significant variation.

1530-nm electroluminescence from p-Ga2S3:Er/n+-Si heterojunctions induced by Zener tunneling

Silicon-based near-infrared (NIR) light sources with a simple structure are significant for circuit integration and fiber optic communications. Herein, 1530-nm electroluminescence (EL) from p-Ga2S3:Er/n+-Si junction light-emitting devices (LEDs) is reported with Er-doped Ga2S3 nanofilms as the photoemission layer and heavily doped n-type silicon as the substrate. The 1530-nm EL emission is attributed to the energy transfer between the Ga2S3 host and the Er3+ dopant, and it reaches its maximum at Er-doping concentration of 1 mol. % as the device works at −4.8 mA. The Er-related NIR EL occurs only at reverse voltages because the holes and electrons for recombination in Ga2S3:Er come from the Zener tunneling in the depletion region and the direct ITO injection, respectively. The realization of 1530-nm p-Ga2S3:Er/n+-Si LEDs offers opportunities for silicon-based integrated light sources.

Spectral study and energy transfer analysis of Er:YAlO3 crystals

Er:YAP crystals have been proved promising mid-infrared gain materials but there is few systematic study focused on the relationship between the doping concentration and spectral properties. In this work, Er:YAP crystals with a series of doping concentrations(0.1 at.%, 1 at.%, 5 at.%, 10 at.%, 15 at.%, 30 at.%) were fast grown successfully by a modified laser-heated pedestal growth (LHPG) method. Through investigating doping concentration dependent spectral characteristics in detail, we found that the cross relaxation process (Er3+: 4S3/2+4I15/2 → 4I9/2+4I13/2) gets significantly enhanced with the doping concentration when it is below 5 at.%, and eventually tends to saturate. And the cooperative up-conversion process (Er3+: 4I13/2+4I13/2 → 4I15/2+4I9/2) conducive to high-efficiency ∼3 μm laser starts to dominate when the doping concentration is 5 at.% or even less. This result demonstrates the potential of Er:YAP crystals to achieve high-power and high-efficiency laser output under relatively low Er-doping concentration, and offers a valuable guidance for doping optimization of Er:YAP systems.

Structure and spectroscopic properties of Er3+ doped LiNbO3 thin film grown by e-beam evaporation

Er3+ doped LiNbO3 (Er: LN) single crystal films with varied doping levels of Er3+ were grown on z-cut LiTaO3 bulk single crystals by using e-beam evaporation method. The crystallographic orientation, fluorescence properties, ions valence states, Er3+ concentration and Li2O content of films were studied. The main phase of the obtained films is determined to be LN from X-ray diffraction and Raman scattering studies, and the films are found to be orienting along (006). Enhancement in the visible and near-infrared luminescence is observed as the doping concentration of Er3+ is increased. The Li2O content of films is determined using the optical birefringence method and found to be at a constant value of 48.8 mol%, which is consistent with the Raman results. XPS results show that the Er concentration in the films is lower than that in the polycrystalline powder since e-beam evaporation has a low efficiency for heavier Er3+. Fluorescence intensity ratios estimated at different measurement temperatures suggest that the Er: LN films have excellent temperature sensitivity, which shows the potential of the films for optical thermometry applications.

Fabrication and Luminescent Properties of Highly Transparent Er:Y2O3 Ceramics by Hot Pressing Sintering.

Highly transparent Er:Y2O3 ceramics (1-9 at.% Er) were fabricated by hot pressing sintering with ZrO2 as the sintering additive. The microstructures, transmittance, luminescent properties, thermal conductivity, and mechanical properties of the Er:Y2O3 ceramic samples were investigated in detail. The samples all exhibited dense and fine grain microstructures; the average grain sizes were about 0.8 μm. The transmittance levels of the samples with various Er concentrations (2 mm thick) at the wavelengths of 600 and 2700 nm were ~74 and ~83%, respectively. As the Er doping concentration increased from 1 to 9 at.%, the up-conversion luminescence of the samples gradually changed from green to red, with the intensity ratio of red/green light increasing from 0.28 to 2.01. Meanwhile, the down-conversion luminescence properties of the specimens were also studied. When the samples were under 980 nm excitation, the emission bands were detected at 1552, 1573, 1639, and 1661 nm. The thermal conductivity of the samples was found to decrease from 8.72 to 5.81 W/(m·K) with an increase of the Er concentration from 1 to 9 at.%. Moreover, the microhardness and fracture toughness of the samples with 1 at.% Er concentration were ~8.51 GPa and ~1.03 MPa·m1/2, respectively.

The effect of Er3+ concentration on the kinetics of multiband upconversion in NaYF4:Yb/Er microcrystals.

In Yb-Er co-doped upconversion (UC) nanomaterials, upconversion luminescence (UCL) can be modulated to generate multiband UCL emissions by changing the concentration of activator Er3+. Nonetheless, the effect of the Er3+ concentrations on the kinetics of these emissions is still unknown. We here study the single β-NaYF4:Yb3+/Er3+ microcrystal (MC) doped with different Er3+ concentrations by nanosecond time-resolved spectroscopy. Interestingly, different Er3+ doping concentrations exhibit different UCL emission bands and UCL response rates. At low Er3+ doping concentrations (1mol%), multiband emission in β-NaYF4:Yb3+/Er3+ (20/1mol%) MCs could not be observed and the response rate of UCL was slow (5-10μs) in β-NaYF4:Yb3+/Er3+. Increasing the Er3+ doping concentration to 10mol% can shorten the distance between Yb3+ ions and Er3+ ions, which promotes the energy transfer between them. β-NaYF4:Yb3+/Er3+ (20/10mol%) can achieve obvious multiband UCL and a quick response rate (0.3µs). However, a further increase in the Er doping concentration (80mol%) makes MCs limited by the CR process and cannot achieve the four-photon UC process (4F5/2 → 2K13/2 and 2H9/2 → 2D5/2). Therefore, the result shows that changing the Er3+ doping concentration could control the energy flow between the different energy levels in Er3+, which could affect the response time and UCL emission of the Yb/Er doped rare earth materials. Our work can facilitate the development of fast-response optoelectronics, optical-sensing, and display industries.

Realization of all-crystalline GaN/Er:GaN/GaN core-cladding optical fiber structures

Erbium-doped gallium nitride (Er:GaN) is a promising gain material for solid-state high-energy lasers operating in the 1.5 μm wavelength window due to the superior optical properties and extremely high thermal conductivity of a GaN host crystal that permit high-power and high-temperature applications. We report the realization of all-crystalline GaN/Er:GaN/GaN embedded waveguide fiber structures using the hydride vapor phase epitaxy growth and re-growth technique, along with chemical–mechanical polishing processes. The Er:GaN core layer possesses an Er doping concentration of 1.7×1020 atoms/cm3, confirmed by secondary ion mass spectrometry measurements. X-ray diffraction measurements confirm, respectively, c-, a-, and m-plane orientations for top/bottom, side, and front/back cross-sectional cladding layers of the fiber structure with good single-crystalline quality. The 1.5 μm Er3+ emission was detected from each surface of the fiber structures via 980 nm resonant excitation. The effect of 1.54 μm light guiding by the fiber structure has been demonstrated. This work laid the foundation toward achieving all-crystalline core-cladding fibers based on GaN wide bandgap semiconductor with potential applications in the harsh environments of high powers, power densities, and temperatures.

Er-doped anatase TiO2 thin films on LaAlO3 (001) for quantum interconnects (QuICs)

Rare-earth ions (REIs) doped into solid-state crystal hosts offer an attractive platform for realizing quantum interconnects that can function as quantum memories and quantum repeaters. The 4f valence electrons of REIs are shielded by 5s and 5p electrons and undergo highly coherent transitions even when embedded in host crystals. In particular, Er3+ has an optical transition in the telecom band that is suitable for low-loss communication. Recently, REIs in thin film systems have gained interest due to potential advantages in providing a flexible host crystal environment, enabling scalable on-chip integration with other quantum devices. Here, we investigate the structural and optical properties of Er-doped anatase TiO2 thin films on LaAlO3 (001) substrates. By choosing a system with minimal lattice mismatch and adjusting Er-dopant concentration, we achieve optical inhomogeneous linewidths of 5 GHz at 4.5 K. We show that 9 nm-thick buffer and capping layers can reduce the linewidth by more than 40%, suggesting a pathway to further narrowing linewidths in this system. We also identify that Er3+ ions mainly incorporate into substitutional Ti4+ sites with non-polar D2d symmetry, which makes Er dopants insensitive to the first order to local electric fields from impurities and is desirable for coherence properties of Er3+ spins.

Improved the stability and enhanced luminescence of Er doped CsPbBr3 perovskite

Cesium lead bromide (CsPbBr3) perovskite has gained significance owing to its potential performance in optoelectronic devices. Here, using the first-principles calculations based on density functional theory, we investigate the effect of Er substitution on Pb atom position on the structural, electronic, and optical properties of CsPbBr3 for improving its luminescence properties. We show that the doping system with highest doping concentration yields the lowest negative binding energy, suggesting that Er doping can enhance the stability of CsPbBr3 well. The calculated band structures indicate that the CsPb1-xErxBr3 system is a p-type semiconductor with the direct bandgap, and the bandgap increases with the increase of Er doping concentration. Interestingly, the Er defect levels obviously appear in bandgap, effectively decreasing the difficulty of the electronic transition. The density of states also show that there are more Er 4f→4f and less Er 4f→Er 5d electronic transition exiting in CsPb1-xErxBr3 system, which are the main origins of luminescence enhancement for CsPbBr3. Furthermore, the optical properties are also analyzed and they imply that the Er doping can improve the optical properties of CsPbBr3 in infrared phonon energy region, and nearly retain the optical properties of CsPbBr3 in other phonon energy region. Our work provides a new luminescence tunable design strategy for Er-doped perovskite materials for the optical communication application.

Effect of the doping concentration of Er3+ on ferroelectric properties of Bi4−xErxTi3O12 films

Effect of the doping concentration of Er3+ on ferroelectric properties of Bi4−xErxTi3O12 films

Preparation of Er:YAG Crystal-Derived All-Glass Silica Fibers For a 1550-nm Single-Frequency Laser

YAG crystal-derived all-glass silica fibers (YDSFs) with different doping concentrations of Er <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3+</sup> were fabricated using the molten-core method. A maximum gain coefficient of 1.46 dB/cm was obtained when an Er:YAG rod at a doping concentration of 5 at.% was used as the precursor material. To the best of our knowledge, this is the highest gain coefficient at the 1.5-μm band in similar YDSFs. The diffusion between the Er:YAG core and silica cladding was investigated during the whole preparation process. Based on the homemade Er <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3+</sup> -doped YDSF, a 1.55-μm pulsed single-frequency YDSF laser was demonstrated for the first time, delivering an output power of 24.2 mW when the absorbed pump power was 174 mW. The corresponding slope efficiency was 15.1%. A single-pulse energy of ~32.7 nJ was obtained with a pulse duration of 78 ns and a repetition rate of 739 kHz. The signal-to-noise ratio was higher than 75 dB.

Third-order nonlinear optical characteristics of Er3+-doped BaMoO4 nanostructures

We report the third order nonlinear optical properties of Er3+-doped BaMoO4 nanostructures, and its dependence on Er-dopant concentration. BaMoO4 nanostructures with different concentration of Er were synthesized by chemical precipitation method and were characterized by UV–Vis absorption, X-ray diffraction (XRD), transmission electron microscopy (TEM) and fluorescence measurements. The incorporation of Er ions shifted the absorption band of BaMoO4 towards higher wavelength and enhanced the light absorption in the visible region. XRD patterns showed that the powders crystallize in scheelite-type tetragonal structure. The nonlinear optical behavior of the nanostructures was investigated by a Z-scan technique at 532 nm using continuous wave Nd:YAG laser. Experimental results suggested that the addition of Er can considerably enhance the nonlinear absorption coefficient and refractive index of BaMoO4 which could be used as a potential for nonlinear optical device applications.

Study of Erbium Doping Effect on Structural, Morphological and Optical Properties of Dip Coated ZnO Under Alkaline Conditions

Undoped Zinc oxide (ZnO) and erbium (Er) doped ZnO thin films have been grown on glass substrate by dip coating technique under alkaline conditions (pH 9). The pH was maintained at 9 for all prepared sols by controlling the amount of Monoethanolamine (MEA). The eff ;ects of Er doping concentration on the ZnO films properties was studied by using XRD, SEM, EDX, AFM, Raman spectroscopy, FTIR analysis and UV–vis spectrophotometer. The results showed that the incorporation of Er3+ under alkaline pH had a great effect on the ZnO properties. All samples exhibit a pure ZnO polycrystalline hexagonal wurtzite structure with a high crystalline quality. Homogenous, smooth and dense granular morphology nanostructures were revealed by AFM and SEM analysis. Raman spectroscopy and FTIR analysis confirm the formation of ZnO hexagonal wurtzite structure for samples. It was found that Er doping concentration enhance optical transmittance of ZnO based thin films. A red-shift was observed in the band gap of Er doped ZnO films with increasing Er concentration. The obtained results make EZO based thin films suitable for solar cells applications.

Synthesis, Structural and Optical Properties of Er and V Codoping ZnO Nanoparticles

Here we are reporting sol–gel synthesis diluted magnetic (Er, V)-co-doped ZnO nanocrystals as a dilute semiconductor. The structural and morphological properties were studied using some techniques such as X-rays diffraction (XRD) and transmission electron microscopy (TEM). The optical properties were characterized by Spectrophotometer UV–Visible–IR and photoluminescence (PL). The structural properties showed the appearance of wurtzite structure with a crystallite size around 45 nm and a secondary phase has been detected, attributed to Erbium complex. Raman measurements show that the good quality of the crystals is also maintained after doping, which is confirmed by the coexistence of the polar and non-polar modes E1 and E2, respectively. The increase in the doping concentration of Er caused a decrease in band gap energy. PL shows the appearance of some defects between the valence and conduction band of ZnO linked to doping with Er.

Electrical and optical characterizations of erbium doped MPS/PANI heterojunctions

Macroporous silicon (MPS) films were yielded by electrochemical anodization of p-type crystalline silicon in HF:DMF. Following, a Schottky structure was obtained by depositing polyaniline (PANI), which was doped with different contents of erbium (Er) using cyclic voltammetry method. The structural analysis showed the formation of pores with diameters ranging between 0.25 and 1.20 μm and length around 15 μm and, after PANI deposition, the diameter became about 17% lower. The chemical characterization by Energy dispersive X-ray spectroscopy (EDS) and Rutherford Backscattering Spectroscopy (RBS) pointed out that the erbium is primarily incorporated at polyaniline surface, but it spreads through the polymer layer and achieves the MPS/PANI interface. According to the Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) analysis, the presence of Er gave rise to the formation of additional functional groups besides that corresponding to polyaniline and silicon oxide phases. The optical characterization within the UV–vis region revealed a modified optical bandgap of PANI as a function of the Er doping concentration. The results of the electrical measurements pointed out to a lowering of the space charge region width in the silicon as well as a change of the PANI workfunction as a function of the Er doping. On the other hand, the current flow through the MPS/PANI Schottky junction was lowered by the increase of the Er doping and by the tunneling mechanism through a thin silicon oxide (≈1–2 nm) grown on MPS during PANI deposition in aqueous solution.

Phase segregation induced third order nonlinear saturable absorption behavior in Erbium doped ZnO nanoparticles synthesized by facile hydrothermal method

Abstract Here in this work, we present the dominance of rare earth dopant (Er) in association with the surfactant (Oleylamine) on the structural, surface morphology, optical, and nonlinear optical properties of hydrothermally grown ZnO nanoparticles. The polycrystalline nature of the prepared nanostructures is confirmed by the XRD diffractograms. The formation of erbium related compound (erbium oxide) in the highest Er doped ZnO nanoparticles is visible from the XRD diffractogram. The incorporation of Er at different doping concentrations (1 at. wt.%, 3 at. wt.%, and 5 at. wt.%) brings noticeable morphological changes in the FESEM images. The Raman spectra reveal the retention of wurtzite structure in undoped and Er doped nanoparticles. The disappearance of A1 (TO) mode in ZnEr3 and ZnEr5 nanoparticles shows the deteriorated polar lattice bond strength. The phase segregation observed from XRD spectrum of ZnEr5 nanoparticles is further confirmed by the detection of local vibrational mode (LVM). A severe decrement in the bandgap of the Er doped nanoparticles is noticed from UV–Vis spectroscopy. A continuous fall in the intensity in the NBE emission with increasing Er doping concentration is attributed to the formation of surface defects below the conduction band edge. The nonlinear optical parameters of the nanoparticles are quantified with the assistance of open aperture and closed aperture Z-scan curves. A remarkable switching from reverse saturable absorption (RSA) to saturable absorption (SA) and self-defocusing to self-focusing mechanisms in ZnEr5 shed light on the impact of phase segregation on the nonlinear response of the Er doped nanoparticles. The quantified values of nonlinear parameters look promising in the fabrication of photonic devices.