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In this paper, the radiation shielding parameters such as linear attenuation coefficients (LAC, µ), mass attenuation coefficients (MAC, µ/ρ), effective atomic numbers (Zeff), effective electron densities (Neff), half value of layers (HVL) and mean free paths (MFP) were investigated for rare earth metal oxides (CeO2 and Er2O3) doped borosilicate (BS) glasses. The glass samples were manufactured by the mechanical alloying process CeO2, Er2O3, and BS powders. The radiation shielding parameters of the BS glass samples were determined at photon energies in the energy region of 22.16–59.54 keV using a high purity germanium detector. The theoretical results for MAC were obtained from WinXCom program. It was observed that theoretical and experimental results are compatible with each other. The radiation absorption increased with increasing the concentration of CeO2 and Er2O3 in the BS samples due to high density increasing with the concentration of CeO2 and Er2O3, which are high atomic mass. Furthermore, LAC, MAC, Zeff, and Neff values for CeO2 and Er2O3 doped BS glass decreased with increasing photon energy. While the MAC value at 59.54 keV energy level for pure BS sample was 0.242 cm2/g, it increased to 0.624 cm2/g with CeO2 addition and 0.838 cm2/g with the addition of Er2O3. The Z eff and N eff values of glass samples with Er2O3 were bigger than CeO2 doped glass samples owing to high atomic number. Consequently, it was determined that BS-Er2O3 glasses had better the radiation shielding capacity than BS-CeO2 glasses. [ABSTRACT FROM AUTHOR]

Under investigation in this paper is a set of the-dimensional nonlinear Schrödinger–Maxwell–Bloch (NLS–MB) equations, which describes the optical pulse propagation in an erbium-doped fibre. Employing the Hirota method and symbolic computation, we obtain the one- two- and N-soliton solutions. We prove that the interactions between the two solitons are elastic through the asymptotic analysis on the soliton solutions. Figures are plotted to show the one soliton and the interaction between the two solitons. We find that the decrease of the frequency shift from the resonance can make the angle between the propagation directions and the amplitudes of the two MB solitons bigger, implying that the change of the amplitudes of the two MB solitons is closely related to the propagation directions of the two NLS solitons. [ABSTRACT FROM PUBLISHER]

The genitourinary syndrome of menopause (GSM) and stress urinary incontinence (SUI) are common clinical challenges for women’s health and quality of life. The laser treatment and particularly the vaginal erbium laser (VEL) may provide a new non-invasive treatment for both GSM and SUI. However, the estimation of the ultimate results of different laser treatments may be altered by different issues, such as patient selection, concomitant treatments, and long-term effect of vaginal laser thermotherapy. In the present paper, we present the protocol for a large multicenter study on the evaluation of the efficacy and safety of VEL for the treatment of GSM and SUI, the Vaginal Erbium Laser Academy Study (VELAS). This study will evaluate the effects of three laser applications in 1500 postmenopausal women. Subjective and objective symptoms will be evaluated prior to the first laser treatment with follow-up visits after 4 weeks from the last laser application, and subsequently after every 3 months for 1 year. Findings from the VELAS have the potential to affect clinical care practice and health decisions for millions of women world-wide for a non-hormonal treatment for GSM and a non-invasive treatment of SUI. [ABSTRACT FROM PUBLISHER]

Graphene oxide mode-locked Er-doped fiber lasers are investigated in this paper. The generalized nonlinear Schrödinger equation, which can be used to describe the fiber lasers, is studied analytically. Soliton solutions for this equation are obtained, and the stable solitons are generated in the fiber lasers. Physical effects, such as the gain bandwidth, distributed gain, group-velocity dispersion, and nonlinearity of fiber lasers, are analyzed. Soliton amplification techniques are proposed which can effectively restrain the appearance of pedestals during the evolution of solitons in the cavity. These analytic results are compared with the experimental ones. The results of this paper will be valuable to the study of the fiber lasers properties and provide theoretical guidance for the obtaining of high-power ultra-short pulses. [ABSTRACT FROM AUTHOR]

In this paper, a multiwavelength two-mode Brillouin fibre laser generated by two-mode optical fibre (TMOF) is proposed and demonstrated experimentally. The system comprises a 500 m long TMOF. A tunable laser source amplified by a high power erbium doped fibre amplifier acts as the Brillouin pump (BP) followed by a single mode fibre Bragg grating as a reflector in the cavity with a centre wavelength of 1544 nm. The BP is observed in the superposition ofandmodes in the few-mode fibre. The set-up is capable of generating a maximum of 12 clearly defined Stokes lines at the pump power of 28.6 dBm, spanning from 1543.88 to 1544.92 nm. [ABSTRACT FROM PUBLISHER]

Using the spray pyrolysis technique, CoSe-doped erbium, and pure cobalt selenide (CoSe) thin film was successfully examined with the influence of deposition temperature. The XRD results revealed that CoSe and CoSe: Er are crystalline materials and as the deposition temperature is increased, the peak intensity is found to decrease. Clusters of sizeable nanoparticles may be seen on the surface micrograph of the synthesised films. They are evenly dispersed and do not exhibit pinholes. The optical studies revealed that CoSe: Er has high absorbance, transmittance, and low reflectance. The obtained energy bandgap ranged from 1.52 to 2.35 eV. It was noticed that doping cobalt selenide with erbium enhances the structural and optical properties of the synthesised films for photovoltaic devices. [ABSTRACT FROM AUTHOR]

In this paper, lanthanum was used as a chemical modifier for the direct determination of erbium by high-resolution continuum source electrothermal atomic absorption spectrometry. A two-step experimental design was used for optimization, first a full factorial design was conducted for identification of significant factors, and then a central composite design was carried out for final optimization of the significant factors. The optimum parameters were obtained as follows: atomization temperature of 2500°C, pyrolysis temperature of 1600°C, and pyrolysis time of 10 s in the presence of lanthanum as a chemical modifier. Under optimum conditions, the characteristic mass, limit of detection, and limit of quantification were 29 pg, 0.71, and 2.4 µg L−1, respectively. The precision of the method, estimated as the relative standard deviation for 10 replicate measurements of 50 µg L−1of erbium, was 1.8%. The optimized method was applied to determine erbium content in sediments and rock samples. The determined values of erbium in sediment certified reference materials were in satisfactory agreement with the certified values according to thet-test for a 95% confidence level. [ABSTRACT FROM PUBLISHER]

The aim of this paper is to present a novel laser technology utilizing the erbium YAG laser for various minimally invasive, non-surgical procedures in gynecology. Non-ablative, thermal-only SMOOTH-mode erbium pulses are used to produce vaginal collagen hyperthermia, followed by collagen remodeling and the synthesis of new collagen fibers, resulting in improved vaginal tissue tightness and elasticity. This erbium laser technology is used for treatments of vaginal laxity, stress urinary incontinence, pelvic organ prolapse and vaginal atrophy. In the period from 2010 to 2014, several clinical studies covering all four indications were conducted with the aim to prove the efficacy and safety of this novel technology. An overview is presented of the results of these studies where several objective as well as subjective assessment tools were used. The results have shown that SMOOTH-mode erbium laser seems to be an effective and safe method for treating vaginal laxity, stress urinary incontinence, pelvic organ prolapses and vaginal atrophy. [ABSTRACT FROM AUTHOR]

In this paper, we construct soliton solutions for a generalized variable-coefficient coupled Hirota–Maxwell–Bloch system, which can describe the ultrashort optical pulse propagation in a nonlinear, dispersive fiber doped with two-level resonant atoms. Under certain transformations and constraints, one- and two-soliton solutions are obtained via the Hirota method and symbolic computation, and soliton collisions are graphically presented and analyzed. One soliton is shown to maintain its amplitude and shape during the propagation. Soliton collision is elastic, while bright two-peak solitons and dark two-peak solitons are also observed. We discuss the influence of the coefficients for the group velocity, group-velocity dispersion (GVD), self-phase modulation, distribution of the dopant, and Stark shift on the soliton propagation and collision features, with those coefficients are set as some constants and functions, respectively. We find the group velocity and self-phase modulation can change the solitons’ amplitudes and widths, and the solitons become curved when the GVD and distribution of the dopant are chosen as some functions. When the Stark shift is chosen as a certain constant, the two peaks of bright two-peak solitons and dark two-peak solitons are not parallel. In addition, we observe the periodic collision of the two solitons. [ABSTRACT FROM AUTHOR]

In this paper, coupled higher order nonlinear Schrödinger–Maxwell–Bloch equations are studied for the ultrashort pulse propagation in erbium-doped birefringent fiber system. Lax pair is constructed for the CHNLS–MB system. Through the Darboux method and symbolic computation, analytic two-soliton solution is obtained. To analyze the specific problem, we design an optimal system by properly choosing the special form of variable coefficients. Here, using obtained two-soliton solution, tunneling of femtosecond soliton through barrier and well is investigated. While solitons are passing through barrier and well, some unexpected behavior is observed and hidden possibilities in switching action through tunneling is investigated. [ABSTRACT FROM PUBLISHER]

In this paper, we develop a complete energy matrices approach investigating the defect structure and EPR parameters ( , , and ) for Er3+ in molybdates. In this approach, the crystal-field parameters used in the calculations are determined from the superposition model and the structural data for tetragonal distortion. The local distortion angles Δθ = −1.628°, Δθ = −1.843° and Δθ = −2.874° are obtained for Er3+ in SrMoO4, PbMoO4 and CaMoO4 crystals, respectively. Moreover, the influence of the orbital reduction factor k and the local distortion angle Δθ on the EPR parameters is analyzed. [ABSTRACT FROM PUBLISHER]

In this paper a tunable single-longitudinal mode (SLM), short-wavelength band (S-band) fiber laser using a conventional erbium-doped fiber (EDF) with a length of 3 m and a step index erbium dopant profile as opposed to the commonly used depressed cladding erbium-doped fiber (DC-EDF) is proposed and demonstrated. The proposed SLM fiber laser has a tuning range of 1496 to 1507 nm in a ring configuration using two 0.15 m of EDF which acts as saturable absorbers (SAs). The highest peak power measured is about −0.6 dBm at a wavelength range of 1502 to 1507 nm. The measured signal-to-noise ratio (SNR) is approximately 74 dB for the same wavelength range. The line-width of the SLM output is measured to be 140 kHz. [ABSTRACT FROM PUBLISHER]

In this paper, we propose and demonstrate a cost-effective wavelength converter utilising a highly nonlinear fibre (HNLF) and a tunable dual-wavelength fibre laser as the pump source. The proposed system uses only the pump source and a signal probe to generate a partially degenerate four-wave mixing (FWM) effect. An FWM conversion efficiency of -12 dB is obtained at pump and signal powers at +13.3 dBm and +5 dBm, respectively, and it is predicted that a higher conversion efficiency is possible if a high power dual-wavelength fibre laser source is used. [ABSTRACT FROM AUTHOR]

The Er-doped YAB (YAl 3 (BO 3 ) 4 ) is a potential self-frequency-doubling laser material. Single crystals were grown by the top-seeded flux method. The absorption spectra of the infrared Er 3+ transitions were monitored in YAB crystals in the 9-300 K temperature range by high-resolution Fourier transform spectroscopy. In the whole spectral range the energy levels and Stark components of 12 transitions were detectable. In this paper the two infrared transitions (from the 4 I 15/2 ground state to the 4 I 13/2 and 4 I 11/2 levels) were analyzed in detail. The low temperature absorption spectra of Er:YAB consist of sharp lines, the number of which corresponds to the theoretical predictions. This suggests that Er 3+ ions occupy one specific lattice site (yttrium positions) with negligible aggregation at the higher dopant concentrations investigated ( i.e. 0.12 Er atom/YAB mole). [ABSTRACT FROM AUTHOR]

In our study, we employed a Mo2TiAlC2 thin film as a passive saturable absorber (SA) to create a stable pulsed fibre laser at 1564.52 nm. We synthesized a Mo2TiAlC2-PVA thin film with a 6% modulation depth and a 10 MW/cm2 saturation intensity. This thin film was integrated into the laser cavity between FC/PC fibre connectors, enabling Q-switching over a pump power range of 30 mW to 120 mW. This resulted in an increased repetition rate from 31.1 kHz to 66.83 kHz and a reduced pulse duration from 13.45 µs to 6.35 µs. The pulse train's stability was confirmed by a high signal-to-noise ratio (SNR) of 58 dB. The laser achieved a maximum output power of 6.56 mW and a pulse energy of 98.16 nJ. These results demonstrate Mo2TiAlC2 as a viable Q-switching modulator in the 1.55-µm wavelength range, with promising applications in compact and efficient pulsed fibre lasers. [ABSTRACT FROM AUTHOR]

We investigate in this paper the influence of intensity-dependent losses on the dynamics of an erbium-doped fibre laser. On the basis of the ion-pair model, it is theoretically demonstrated that this feedback efficiently suppresses the self-pulsing occurring in heavily doped fibre lasers. [ABSTRACT FROM AUTHOR]

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Erbia-credit super high burnup (Er-SHB) fuel offers a means to introduce >5 wt% 235U enrichment fuel; small amounts of erbia added to all the high-enriched U02 powder can reduce the initial reactivity to <5 wt% enrichment level. By using this erbia credit, the new fuel can be treated as <5 wt% enriched fuel, and most modifications to the existing facilities and equipment can be avoided. One of the key issues for developing the Er-SHB fuel is to validate the criticality safety analysis tools for this fuel based on a series of experiments using fuel with small amounts of erbia in the entire core. For that purpose, a series of critical experiments have been performed at the Kyoto University Critical Assembly (KUCA). Four critical cores were constructed utilizing two different average enrichments, three different erbia contents, and four different H/U ratios. Numerical analyses have also been performed using several different cross-section libraries, and the results were compared with the measurements from the KUCA experiments. These results confirm the validity of the calculations and the cross-section libraries for determining erbia reactivity. This paper outlines the basic concepts of the Er-SHB fuel, the erbia experiments, and the analyses results. [ABSTRACT FROM AUTHOR]

IRIS is a 335-MW(electric) pressurized water reactor (PWR) with integral primary system. Its design and optimized maintenance are compatible with long cycles, up to 4 yr. Advanced fuel management techniques are employed to support this objective; among others, novel use of burnable absorbers is considered. Erbium is one absorber that is currently utilized in PWRs. It has many desirable properties that ideally suit the extended cycle and low soluble boron concentration targeted by IRIS. However, erbium also leads to a cycle length penalty due to incomplete depletion and residual absorber isotopes, plus uranium displacement following erbium incorporation in the fuel matrix. This paper proposes to consider modifying the isotopic composition of erbium, evaluates its impact, and demonstrates that it is possible to obtain a considerable reduction of the penalty while retaining the positive features of natural erbium fuel. The economic benefit of the reduced penalty is appealing for the industrial production of isotopically modified erbium fuel. [ABSTRACT FROM AUTHOR]

We propose a coupled system of generalized nonlinear Schrödinger and Maxwell–Bloch equations with variable coefficients which describes propagation of an optical soliton in an inhomogeneous nonlinear waveguide doped with two-level resonant atoms. The Lax pair of this model is derived using the Ablowitz–Kaup–Newell–Segur (AKNS) formalism. The one-soliton solution is constructed through a Darboux–Bäcklund transformation (BT). The coupled system is found to allow soliton propagation. We explain the soliton control by the effect of distributed amplification with varying group velocity dispersion, nonlinearity and gain or loss parameters. [ABSTRACT FROM AUTHOR]

The gadolinium tungsten borate glasses doped with Er3+ were prepared by melt quenching technique for study in physical, absorption and luminescence properties. The glass composition (30-x) B2O3 − 27.5 Gd2O3 − 42.5 WO3 – x Er2O3, where x = 0.1, 0.5, 1.0 and 2.0 mol%. The results show that doping Er2O3 in higher concentration make the glass density and molar volume increases. The absorption spectra indicate the photon absorbing of Er3+ in visible light and near-infrared region. The emission spectra of these glasses have been recorded under 275 nm (Gd3+) and 380 nm (Er3+) excitation wavelength and it is observed that these glasses show green 550 nm and red 577 nm. NIR photoluminescence under 311 nm (Gd3+), 524 nm (Er3+) and 978 nm (Er3+), excitation was measured of glass in the region 1400–1700 nm. NIR emissions show a peak centered at 1543 nm. The luminescence of an erbium-doped glass was investigated at room temperature. In addition, mechanisms of the luminescence by multiphoton absorption and energy transfer processes are discussed based on the energy-level diagram of Er3+ and luminescence spectra. These results benefit for efficient short and conventional-length optical amplifiers and tunable lasers. [ABSTRACT FROM AUTHOR]

Adsorption offers an efficient and eco-friendly method for the recovery of rare earth elements (REEs). However, it is not well known that most adsorbents are not eco-friendly. Rational design of next generation adsorbents should aim to enhance their green properties. In this work, sepiolite, Fe3O4 and itaconic acid were selected as the green raw materials. Poly(itaconic acid)/magnetite sepiolite composite (PIA/MSEP) was prepared using water as the solvent under mild reaction conditions and the entire process uses neither the bulk use of toxic organic solvents nor the addition of dangerous strong acid or alkali. The results indicate that PIA/MSEP has satisfactory maximum adsorption capacities of 178.57, 151.52 and 106.38 mg·g−1 for Er3+, Nd3+ and Ce3+, respectively, with excellent regeneration stability. The PIA/MSEP exhibits outstanding adsorption rates that provide above 90% capacity within 10 min for Er3+ and Nd3+. This versatile material is a potential candidate for applications in the removal of REEs. [ABSTRACT FROM AUTHOR]

This aim of this study was to determine the effect of 1540-nm nonablative fractional erbium on macular amyloidosis. This phase-II clinical trial study has been performed with parallel group with blinding of the evaluator. The skin lesions of the patients (15 patients and 30 lesions) with cutaneous macular amyloidosis were randomly assigned into laser and no-treatment groups. In the laser group, treatment was performed by 1540-nm nonablative fractional erbium laser. Thereafter, the patients' lesions were compared in terms of pigmentation, rippling, thickness, and subjective response. The lesions of the intervention group significantly improved in the three-month follow-up compared to the control group (in the control and intervention group, improved pigmentation was observed in 20 and 53.3% with p =.02, improved rippling in 6.7 and 60% with p =.007, diminished lichenification in 0 and 53.1% with p =.007, and overall lesion improvement in 20 and 60% with p =.03, respectively). In investigating the subjective response through patient global assessment, the patients in the intervention group had a greater satisfaction (p =.01). There was a considerable improvement of pruritus in the intervention group (p =.001). Use of 1540-nm nonablative fractional erbium laser offered a suitable efficacy to treat macular amyloidosis without significant complications. [ABSTRACT FROM AUTHOR]

In this work, multi wall carbon nanotube (MWCNT) doped borate glass has been successfully developed by melt quenching technique with the chemical composition 67.5B2O3-20ZnO-12Gd2O3-Er2O3-0.5MWCNT. Several peaks observed from absorption spectra due to transition from 4I15/2 as a ground state into several states i.e. 4G11/2, 2G9/2, 4F7/2, 4F5/2, 2H11/2,4S3/2, 4F9/2, 4I11/2, and 4I13/2. The sample shows a strong emission in 1536 nm because of 4I13/2→4I15/2 transition under 520 nm wavelength excitation. Emission around 402 nm and 471 nm under 270 nm excitation could be the indication for presence of MWCNT. The sample exhibits NIR to NIR up-conversion under 1500 nm excitation. Absorption data have been used to calculate optical band gap energy through Tauc plot method. This study shows that MWCNT doped borate glass could be a promising material for solid state application in NIR region. [ABSTRACT FROM AUTHOR]

A new compact and wide-band erbium-doped fibre amplifier (EDFA) was demonstrated by combining Hafnia-bismuth Erbium co-doped fibre (HB-EDF) and zirconia–yttria–aluminum Erbium co-doped fibre (Zr-EDF) as a hybrid gain medium, in parallel double-pass configuration. The proposed amplifier comprises a 0.5 m long HB-EDF and 4 m long Zr-EDF optimized for C- and L-band operations, respectively. The HB-EDF and Zr-EDF has erbium ion concentration of 12,500 ppm and 2800 ppm, respectively. At -10 dBm input signal, a wide-band flat gain of 15.7 dB is achieved with gain fluctuation of less than 1.5 dB within a wavelength region from 1525 to 1600 nm. Compared to same configuration of HB-EDF and Zr-EDF amplifiers which are using two pieces of HB-EDF and Zr-EDF, respectively with the same total amount of erbium ions, the proposed EDFA with hybrid gain medium provides even better performances in term of flat gain, bandwidth and noise figure. [ABSTRACT FROM AUTHOR]

Upconverting nanoparticles can be excited by near-infrared light and have a high tissue penetration depth, and have a wide range of applications in the field of bioimaging. The commonly prepared NaYF4:Yb,Er are oil soluble, which limits their further biological applications and requires surface modification. In this article, we describe in detail the methods of PVP-modified NaYF4:Yb,Er and successfully modify oil-soluble NaYF4:Yb,Er to be water-soluble. [ABSTRACT FROM AUTHOR]

A special target structure for erbium (Er)-zirconium (Zr) co-deposition is proposed, based on the hollow cathode effect. To study the effect of rare earth on the alloyed layer, Zr-Er alloyed layers with different quantity proportion of Er and Zr elements were prepared on Ti-based substrate using double glow plasma surface alloying. The microstructure and composition of the alloyed layers were analysed by XRD and SEM-EDS. Results showed that Er element grows perpendicular to the Ti-based substrate in the alloyed layers, and it was found that the growth structure had an opposite effect on the diffusion of the Zr element. Interestingly, as the concentration of Er element increases, the addition of Er element to a certain extent affects the crystallisation of the Zr-Er alloyed layer and reduces the diffusivity of the Zr element. [ABSTRACT FROM AUTHOR]

A C-band mode-locked fibre laser incorporating a boron nitride-doped graphene oxide (BN-GO)-based saturable absorber (SA) is proposed and demonstrated. The SA is fabricated by depositing multiple layers of synthesized BN-GO nanoparticles onto the polished surface of a side-polished fibre, which is then inserted into an erbium-doped fibre laser cavity to generate the desired pulsed output. The strong nonlinear optical response and light absorption of the BN-GO nanoparticles induces the generation of a highly stable mode-locked pulse at 1567.32 nm with visible Kelly’s sidebands. The pulses have a measured repetition rate of 13.56 MHz and a pulse width of 1.18 ps at the maximum pump power of 280.5 mW. The pulses have a frequency signal-to-noise ratio of ∼53 dB, indicating a highly stable output. The proposed laser would find significant telecommunications applications, particularly for dense wavelength division multiplexing systems. [ABSTRACT FROM AUTHOR]

A novel erbium-doped fibre amplifier (EDFA) test bed is designed using the dominant technical MATLAB Simulink platform to characterize gain, noise figure and amplified spontaneous emission (ASE) power variations of a forward pumped EDFA operating as functions of amplifier length, injected pump power, signal input power and doping density in the C-band (1525-1560 nm). The numerical modelling of the rate and propagation equations is done. The Simulink model for two-level-based analysis is designed to investigate the dynamic characteristics of an EDFA. A significant addition to the model is the ability to handle multiple channels using the absorption and emission coefficients that vary as per different specifications and the quantum well laser is being modelled to be applied as the pump source. The results are shown and analyzed graphically for designated simulation environment that accurately represents EDFA performance metrics such as gain, population inversion factor , noise figure, quantum conversion efficiency and power conversion efficiency. The present model can be implemented successfully as a test bed to study the EDFA dynamics over the entire third optical communication bandwidth (1525-1690 nm) with the ability to analyze and optimize all the parameters to achieve the desired operating performance before actual physical designing of device as per the application. [ABSTRACT FROM AUTHOR]

Based on first-principles calculations, we have studied the crystal, electronic structure and optical properties in both wurtzite and zinc blend structure of AlN doped with rare-earth element Er. The calculations indicate that the lattice parameters increase after doping showing the distortion of the crystal structure and its density of states is obviously asymmetric indicating the sample is magnetism. The static dielectric constant ε1(0) of doped systems are increasing compare with pure AlN and the value of zinc blend structure Al0.75Er0.25N is biggest than that of other structures. Dielectric imaginary part ε2(ω) and absorption coefficient I(ω) both show red shift and the absorption enhance in visible region after doping. [ABSTRACT FROM AUTHOR]

We derive the analytical rogue wave solutions for the generalized inhomogeneous nonlinear Schrödinger-Maxwell-Bloch (GINLS-MB) equation describing the pulse propagation in erbiumdoped fibre system. Then by suitably choosing the inhomogeneous parameters, we delineate the tunneling properties of rogue waves through dispersion and nonlinearity barriers or wells. Finally, we demonstrate the propagating characteristics of optical solitons by considering their tunneling through periodic barriers by the proper choice of external potential. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the long-term efficacy of a second generation of vaginal laser treatment, the vaginal erbium laser, as a non-ablative photothermal therapy for the management of genitourinary syndrome of menopause.Methods: The study was performed using an erbium laser crystal yttrium-aluminum-garnet (XS Fotona Smooth™, Fotona, Ljubljana, Slovenia) with a wavelength of 2940 nm. Postmenopausal women (n = 205) were treated with three laser applications at 30-day intervals. Symptoms were assessed before and after treatment throughout 24 months, using the subjective visual analog scale (VAS) and the objective vaginal health index score (VHIS). In addition, postmenopausal women suffering from stress urinary incontinence were evaluated with the International Consultation on Incontinence Questionnaire-Urinary Incontinence Short Form (ICIQ-UI SF).Results: Vaginal erbium laser treatment induced a significant (p < 0.01) decrease in VAS for both vaginal dryness and dyspareunia, as well an increase in VHIS (p < 0.01) up to the 12th month after the last laser treatment. The values returned to levels similar to the baseline after 18 and 24 months. In addition, vaginal erbium laser treatment improved mild-moderate stress urinary incontinence in 114 postmenopausal women. Less than 3% of patients discontinued treatment due to adverse events.Conclusions: These results suggest that vaginal erbium laser may be effective and safe for the treatment of genitourinary syndrome of menopause. [ABSTRACT FROM AUTHOR]

Ytterbium, erbium, aluminum tri-doped zinc oxide crystal was synthesized, which can turn color from red to green up-conversion luminescence through adjusting aluminum content. When the aluminum concentration reached 4 mol%, the color of up-conversion emission first turn from red to green. Meanwhile, the ratio of red to green emission reduced from 25.32 to 0.26, and the coordinates of chromaticity coordinate calculation changes from (0.5749, 0.3378) to (0.2190, 0.7169) with aluminum concentration range from 0 to 4 mol%. The up-conversion emission peaks at 521, 542, and 660 nm of sample originate from the transitions of2H11/2→4I15/2,4S3/2→4I15/2, and4F9/2→4I15/2of erbium ions, respectively. X-ray diffraction patterns perform the better crystallization degree with increasing aluminum concentration. The scanning electron microscopy images show the porous and lamellar structures with different aluminum concentrations. A convenient but effective design to obtain ytterbium, erbium, aluminum tri-doped zinc oxide up-conversion luminescence is reported, which can turn color from red to green. [ABSTRACT FROM PUBLISHER]

We demonstrate a Q-switched Erbium-doped fibre laser (EDFL) utilizing cobalt oxide (Co3O4) nanocubes film based saturable absorber (SA) as a passive Q-switcher. Co3O4nanocubes are embedded into a polyethylene oxide film to produce a high nonlinear optical response, which is useful for SA application. It has saturation intensity and modulation depth of 3 MW/cm2and 0.35%, respectively. The proposed laser cavity successfully generates a stable pulse train where the pulse repetition rate is tunable from 29.8 to 70.92 kHz and the pulse-width reduces from 10.9 to 5.02 μs as the 980 nm pump power increases. This result indicates that the Co3O4is excellent for constructing an SA that can be used in producing a passively Q-switched fibre laser operating at a low pump intensity. To the best of our knowledge, this is the first demonstration of Co3O4film based fibre laser. [ABSTRACT FROM PUBLISHER]

Background:Fractional ablative lasers have recently been used for the treatment of skin scars. The objective of this study was to assess the efficacy and safety of the fractional erbium-doped yttrium aluminum garnet (Er:YAG) laser (2940 nm) in the treatment of skin scars.Materials and methods:A total of 9 patients (8 female, 1 male) with Fitzpatrick skin types III and IV suffering from atrophic facial acne scars were treated with a fractional Er:YAG laser for 2–5 (mean 3.3) sessions 4–6 weeks apart. One independent investigator assessed the efficacy, using standardized photographs, before and 1 month after the last treatment. The patients’ satisfaction rate was also evaluated.Results:The treatment was well tolerated by all patients without any anesthesia. The downtime was 2–3 days. All patients showed improvement in scars: excellent in 1, good in 1, and fair in 7 patients. Six patients were highly satisfied and 3 were satisfied with treatment. No adverse effect was noted.Conclusion:A fractional Er:YAG laser can deliver an effective and minimally invasive treatment for acne scars. [ABSTRACT FROM PUBLISHER]

Background: Non-ablative fractional lasers have been effectively used in skin rejuvenation. Objectives: This study evaluates the efficacy of 1550-nm Erbium glass laser for facial rejuvenation through the correlation of clinical evaluation and histopathology, immunohistochemistry, and electron microscopy analysis. Methods: Fifteen subjects (average age: 56.4 years, skin types: I–III) with mild-to-moderate photodamage were submitted to biopsies and 3 facial treatments. Data from the photo assessments and the clinical improvement were analyzed 4 months after the treatments. The biopsy skins were fixed in neutral buffered formalin before being embedded in paraffin, and stained with hematoxylin and eosin. The histomorphometric quantification of collagen and elastic fibers; intercellular adhesion molecule 1 expression by immunohistochemistry; and analysis of cell cycle phases, the electrical potential of the mitochondrial, and interleukin (IL)-1, CD34, transforming growth factor (TGF)-β, and caspase-3 expression by flow cytometry were analyzed. Results: After 4 months of treatment, collagen fibers had increased by 6.68%, and intercellular adhesion molecule 1 (ICAM-1) had increased by 4.47% in vessel area. Significantly enhanced IL-1 and TGF-β receptor expressions were identified after treatment. Proliferative responses and non-apoptosis-dependent caspase-3 activity were both observed in the cell after dermal treatment. Conclusion: The histopathology, immunohistochemistry, and electron microscopy showed an improvement compatible to the clinical effectiveness after 4 months. [ABSTRACT FROM AUTHOR]

Janus particles are mainly composed of synthesis polymer. Herein, the natural product of urushiol is used to fabricate Janus particles. The erbium ion absorbed on polystyrene (PS) reacted with urushiol and then the urushiol-erbium chelate polymer (UEr) shell formed. The UEr-PS Janus particles originated from the swelling of UEr/PS core-shell structure. The UEr-PS Janus particles were compartmentalized into two parts with different morphologies and chemical compositions. The thickness of the UEr shell could be controlled by adjusting sulfonated time. The UEr-PS Janus particles possess the characteristics of urushiol and erbium, which can be used in oriented materials. [ABSTRACT FROM PUBLISHER]

Background:Acne scars are often a permanent disfiguring sequel of acne vulgaris. Although many treatment modalities are available, they are often non satisfactory for all patients.Objective:To determine the effectiveness and safety of fractional 1540 nm erbium_glass laser treatment of facial acne scars in Iraqi patients.Patients and methods:Twenty one patients were enrolled in this prospective clinical study. Three sessions of the 1540 nm erbium glass laser were applied at 2-week intervals. The patients were assessed at 1, 3, and 6 months after the last session. The effect of treatment was assessed by objective (Sharquie scoring system for grading acne scarring and visual analog scale) and subjective (patient satisfaction) methods.Results:Two patients were defaulted. Eleven patients (57.9%) showed improvement from moderate to mild grade, and no grade changes were detected in eight patients (42.1%). The mean score of the visual analog scale prior to treatment was 8.61 ± 0.86 and decreased to 6.15 ± 1.28 (P= 0.037). Ten patients were satisfied to varying degrees. No significant side effects were noted.Conclusion:Non-ablative fractional 1540 nm erbium glass laser is an effective and safe method to treat acne scars and represent good alternative for patients who cannot use the ablative methods because of its longer downtime. [ABSTRACT FROM AUTHOR]

LaOCl:Yb3+, Er3+nanobelts were prepared by electrospinning combined with a double-crucible chlorination technique using NH4Cl as chlorinating agent. X-ray powder diffraction analysis indicated that LaOCl:Yb3+, Er3+nanobelts were tetragonal with space group P4/nmm. Scanning electron microscope analysis and histograms revealed that width of LaOCl:Yb3+, Er3+nanobelts was 6.12 ± 0.18 μm under the 95% confidence level, and the thickness was 113 nm. Transmission electron microscope observation showed that as-obtained LaOCl:Yb3+, Er3+nanobelts were composed of nanoparticles. LaOCl:Yb3+, Er3+nanobelts emitted strong green and red up-conversion emission centring at 523, 551 and 667 nm, respectively, attributed to2H11/2→4I15/2,4S3/2→4I15/2and4F9/2→4Il5/2transitions of Er3+under the excitation of a 980-nm diode laser (DL) excitation. Moreover, the near-infrared characteristic emission of LaOCl:Yb3+, Er3+nanobelts was achieved under the excitation of a 532-nm laser. Commission Internationale de L'Eclairage analysis demonstrated that colour-tuned luminescence can be obtained by changing doping concentration of Yb3+and Er3+, which could be applied in the fields of optical telecommunication and optoelectronic devices. The up-conversion luminescent mechanism and the formation mechanism of LaOCl:Yb3+, Er3+nanobelts were also proposed. [ABSTRACT FROM PUBLISHER]

Background: Aging of the neck skin includes poikiloderma of Civatte, skin laxity and wrinkles. While the vascular alterations of poikiloderma of Civatte can be effectively treated with lasers or intense pulsed light, a successful treatment of dyschromia, skin laxity and wrinkles is still difficult to achieve. Objective: To evaluate the safety and efficacy of non-ablative fractional 1540 erbium glass laser for the treatment of aged neck skin, also by means of in vivo reflectance confocal microscopy (RCM). Methods: A prospective study for neck resurfacing in 18 women with aged neck skin. Six laser treatments were performed in 4-week intervals with a 1540-nm erbium-glass fiber laser. Results: By using a 6-point grading scale, the mean score (±SD; range) at baseline was 3.6 (±1.5; 1-6) for skin dyschromia, 2.9 (±1.4; 1-6) for laxity and 3.3 (±1.3; 1-5) for wrinkles. Three months after the last laser session, we found a significant clinical improvement of dyschromia ( p = 0.0002; Wilcoxon test), and wrinkles ( p = 0.0004; Wilcoxon test), with a mean (±SD) reduction of 2.5 (±1.0) and 1.9 (±1.1) points in the 6-point grading scale, respectively. No change was observed in laxity. These results were also supported by structural changes documented by RCM. Conclusion: Non-ablative fractional 1540 erbium glass laser was both safe and effective for the treatment of dyschromia and wrinkles, but not effective for the laxity of the neck skin. [ABSTRACT FROM AUTHOR]

This study demonstrates simulation and experimental validation of a wideband serial hybrid Raman/erbium-doped fiber amplifier. Two configurations are adopted; in type A, a Raman amplifier is the first stage, and in type B, an erbium-doped fiber amplifier is the first stage. At low input signal power, the average gain level is 20 dB with a flat gain bandwidth of 40 nm for both configurations. The noise figure in type B is dominated by the erbium-doped fiber amplifier and produces lower values and flatter spectra than in type A. The gain of the proposed hybrid amplifiers is affected more by the second amplification stage. [ABSTRACT FROM PUBLISHER]

A co-doped LiNb0.3Ta0.7O3:Er3+,Yb3+ceramic was prepared by a high temperature solid state procedure. Under the excitation of 980 nm laser radiation, intense 660 nm red light and 550 nm green light emissions corresponding to the4F9/2→4I15/2and2H11/2/4S3/2→4I15/2transitions of Er3+were observed. The change of Yb3+concentration has a more significant influence on luminous intensity than the Er3+concentration. The emission of red and green lights is attributed to a two-photon process. The upconversion luminescence mechanisms were analyzed in detail. [ABSTRACT FROM AUTHOR]

Background: Xanthelasma palpebrarum (XP) is characterized by soft, yellow plaques on the upper or lower eyelids that create aesthetic problems for patients. There are several methods in the treatment of XP, such as surgical excision, blepharoplasty, cryotherapy, electrocauterization, chemical cauterization using trichloroacetic acid (TCA) or bichloroacetic acid and laser ablation. Objective: To evaluate the efficiency and complications of 70% TCA application versus erbium: YAG laser ablation in different XP lesions on the same patient. Methods: A total of 21 patients were taken into the study-1 male and 20 females, from ages 22 to 70 years. Erbium: YAG laser ablation and 70% TCA application were performed in different XP lesions of the same patient. All patients were photographed before initiating treatment and after 4 weeks using the same digital camera. Evaluation was performed 4 weeks after the first treatment session by comparing pre-treatment and post-treatment photographs by two independent dermatologists. Results: No significant difference of the improvement scores between the erbium laser and TCA was found ( p = 0.248). No significant difference between the complication scores using erbium laser and TCA was found ( p = 0.739). Conclusions: Both 70% TCA application and erbium: YAG laser ablation methods have similar effectiveness and complication rates. [ABSTRACT FROM AUTHOR]

A simple multi-wavelength passively Q-switched Erbium-doped fiber laser (EDFL) is demonstrated using low-cost multi-walled carbon nanotubes (MWCNTs)-based saturable absorber, which is prepared using polyvinyl alcohol as a host polymer. The multi-wavelength operation is achieved based on non-linear polarization rotation effect by incorporating 50?m long photonic crystal fiber in the ring cavity. The EDFL produces a stable multi-wavelength comb spectrum for more than 14 lines with a fixed spacing of 0.48?nm. The laser also demonstrates a stable pulse train with the repetition rate increasing from 14.9 to 25.4?kHz as the pump power increases from the threshold power of 69.0?mW to the maximum pump power of 133.8?mW. The minimum pulse width of 4.4??s was obtained at the maximum pump power of 133.8?mW while the highest energy of 0.74 nJ was obtained at the pump power of 69.0?mW. [ABSTRACT FROM AUTHOR]

We demonstrate a self-seeded multi-wavelength Brillouin–erbium fibre laser with double Brillouin frequency gap. The twice channel gap is induced by the gain difference in different directions. Thirty-six stable output channels with 20?GHz frequency gap are obtained when the 980?nm pump power is 300?mW. The factor that induces the double frequency gap is investigated and proved. [ABSTRACT FROM AUTHOR]

Erbium-activated silica-titania and silica-hafnia planar waveguides have been prepared by the sol-gel route. The films were deposited on vitreous silica substrates using a dip-coating technique. The parameters of preparation have been chosen to optimize the waveguides for operation in the near-infrared (NIR) region and to increase the luminescence efficiency of the metastable4I13/2state of erbium ions. The waveguides’ properties were determined by m-line spectroscopy and loss measurements. Waveguide Raman and luminescence spectroscopy were used to obtain information about the structure of the prepared films and about the dynamical process related to the emission in the C telecom band (1530–1565 nm) of the erbium ions. The results are discussed with the aim of comparing the structural and optical properties of erbium-activated silica-titania and silica-hafnia planar waveguides. [ABSTRACT FROM PUBLISHER]

We demonstrate a simple, compact, and low cost mode-locked erbium-doped fiber laser (EDFL) using a single-walled carbon nanotubes (SWCNTs) embedded in polyethylene oxide (PEO) thin film as a passive saturable absorber (SA). The film with a thickness of 50 μm was fabricated using a prepared homogeneous SWCNT solution with 0.1% loading percentage, which was mixed with a diluted PEO solution and casted onto a glass Petri dish to form a thin film by evaporation technique. The film is sandwiched between two fiber connectors to construct a SA, which is then integrated in an EDFL cavity to generate a self-started stable soliton pulses operating at 1558 nm. The soliton pulse starts to lase at pump power threshold of 17.6 mW with a repetition rate of 50 MHz, pulse width of 0.67 ps, average output power of 0.158 mW, pulse energy of 3.16 pJ, and peak power of 4.43 W. [ABSTRACT FROM AUTHOR]

An all-fiber amplification and compression system seed is demonstrated by using a chirped pulse oscillator at the telecommunication band. Dispersion management is applied successfully both in the oscillator and amplifier, allowing dissipative soliton (DS) generation and amplification. The oscillator generates 4-ps chirped pulses with 130 mW (4.55 nJ) average power. Benefiting from large chirp and the high energy of DSs from the oscillator, the amplification system can be simplified. The average power after amplification is increased to 324.2 mW, corresponding to a single pulse energy of 11.3 nJ. The minimum pulse duration is 190 fs after the single-mode fiber (SMF) is employed to compress the pulses. The repetition rate of pulses is 28.6 MHz. [ABSTRACT FROM AUTHOR]

Wavelength division multiplexing (WDM) systems, which are widely used in telecommunication, have the advantages of huge bandwidth support and reliability. A performance analysis is presented of a WDM system using an erbium-doped fiber amplifier (EDFA), with specific emphasis on bit error rate (BER) optimization. EDFA parameters, including doped fiber length and pump power, are optimized and performance evaluating parameters for different modulation schemes are observed. Simulation results provide optimized BER, noise figure, and gain flatness values. The WDM system is modeled from 1546 nm to 1558 nm bandwidth to obtain maximum gain uniformity, low noise figure, and low BER. This wavelength range is selected to investigate the 1550 nm wavelength commonly used in the telecommunication industry. Also, that we are using a WDM grid, so multiple channels can be accommodated in this range. [ABSTRACT FROM AUTHOR]