Development Of Solid-state Lasers Research Articles

High power and short wavelength: The route for the development of solid-state lasers

High power and short wavelength: The route for the development of solid-state lasers

Influence of PbF2 content on optical thermometry of Er3+/Yb3+ co-doped tungsten sodium phosphate glasses

Abstract The green emissions of the trivalent erbium ions exhibit promising applications in photonics, such as the development of solid-state lasers, optical sensors, and light-emitting diodes (LED). In this work, the intensity of the emissions of two thermally coupled levels 2H11/2 and 4S3/2 excited states of Er3+ ions are studied in Er3+/Yb3+ co-doped tungsten sodium phosphate oxyfluoride glasses. The results demonstrate that an increase in the content of the PbF2 leads to an enhancement in the performance of these samples as optical sensors, and amplifies the relative thermal sensitivity from 0.82% K−1 to 1.15% K−1 for glass samples containing 10 mol% and 50 mol% of PbF2, respectively. Additionally, the effect of PbF2 is discussed in terms of the modifications of the site symmetries around Er3+ ions and changes in the energy gap between the thermally coupled levels, which implied in the improvement of the absolute thermal sensitivity at higher temperatures for high PbF2 contained sample.

Visible emission studies of melt-grown Dy-doped CsPbCl3 and KPb2Cl5 crystals

We report results of the optical properties of Dy-doped CsPbCl3 and KPb2Cl5 bulk crystals for potential applications in yellow solid-state laser development. The crystals were synthesized from purified starting materials and melt-grown by vertical Bridgman technique. Optical transmission measurements revealed characteristic absorption bands from intra-4f transitions of Dy3+ ions. Direct optical excitation at 455 nm (6H15/2 → 4I15/2) resulted in dominant yellow emission bands at ∼575 nm from the 4F9/2 excited state of Dy3+ ions. In addition, both crystals exhibited weaker emission lines in the blue (∼483 nm) and red (∼670 nm) regions. The peak emission-cross sections for the yellow transition (4F9/2 → 6H13/2) were determined to be ∼0.22 × 10−20 cm2 for Dy: CsPbCl3 (λpeak = 576.5 nm) and ∼0.59 × 10−20 cm2 for Dy: KPb2Cl5 (λpeak = 574.5 nm). The spectral properties and decay dynamics of the 4F9/2 excited state were evaluated within the Judd-Ofelt theory to predict total radiative decay rates, branching ratios, and emission quantum efficiencies.

Role of Sm<sup>3+</sup> on Mn Nanoparticles Embedded Zinc Tellurite Glasses Absorption and Luminescence Characteristic

Enhancing the optical performance of rare earth doped binary inorganic glasses is an ever-demanding quest. Samarium (Sm3+) doped zinc tellurite glasses containing Manganese (Mn) nanoparticles (NPs) with composition (59-x)TeO2-20ZnCl2-10ZnO-10Li2O-1Sm2O3-(x)Mn3O4, where x = 0 to 0.06 mol% are prepared by melt quenching technique. The role played by Mn NPs in enhancing the optical behaviors are analyzed and discussed. The XRD patterns confirm the amorphous nature of the glass. The UV-Vis-NIR spectra reveal seven prominent absorption bands of Sm3+ ions. The photoluminescence spectra display four peaks corresponding to 4G5/2→6H5/2, 4G5/2 →6H7/2, 4G5/2→6H9/2 and 4G5/2 →6H11/2 transitions. An enhancement in the luminescence intensity is observed up to 0.05 mol% concentration of NPs and the intensity quenches beyond it. The enhancement is attributed to local electric field effect of NPs in the proximity of Sm3+ ion. Our results on improved optical response via precise control of NPs contents may be useful for the development of solid state lasers and amplifiers.

Intrinsic Magnetic and Ferroelectric Behaviour of Non-magnetic Al3+ Ion Substituted Dysprosium Iron Garnet Compounds

Synthetic garnets are a group of oxide materials that play a vital role in the development of solid state lasers, magnetic and optic-electronic devices. The analysis on the solubility of rare-earth elements in the well-crystallized system has led to the discovery of peculiar oxide materials with multifunctional properties. By following the above importance, Aluminium ion (Al3+) substituted Dysprosium Iron Garnet compounds with the chemical formula of Dy3Fe5−xAlxO12 (x = 0–0.5) have been synthesized by the solid state reaction method and the effect of substitution of non-magnetic ions into the magnetic sub-lattices have been analyzed. The Rietveld refinement of powder x-ray diffraction patterns confirms that the pure Dy3Fe5O12 compound crystallizes with cubic (Space group: Ia3d) superstructure whereas all the Al3+ substituted samples exhibit the coexistence of cubic (Ia3d) and trigonal Fe2O3 (R3c) phases. The energy gap values of the prepared compounds is found to be around 1.6 eV which reveals the semiconducting nature and the decreasing trend of band gap values may be due to the growth factor of crystallites, structural disorder and distortion introduced into the crystal lattice. From the Micro-Raman analysis, it is found that the substituted Al3+ ions starts filling into both tetrahedral and octahedral positions and the assignments of vibrational modes observed from Raman spectra confirm the incorporation of Al3+ ions into the Dy3Fe5O12 garnet structure. From the magnetization analysis, it is found that the response of super-exchange interaction between Fe3+ ions in the a and d sites of Dy3Fe5O12 compound leads to net magnetic moment and the substitution of Al3+ ions preferably replaces Fe3+ ions in d sites and suggests the decrease in net magnetization values. From the photoluminescence studies, it is noticed that the luminescence behavior of Al3+ ions substituted Dy3Fe5−xAlxO12 compounds are due to the superposition of a broad emission band and reveals the variation in concentration of Al3+ ions in the prepared compounds. An interesting point to note is that, a well saturated “soft” ferroelectric hysteresis loop is obtained in both pure and Al3+ substituted Dy3Fe5−xAlxO12 compounds, and the observed electric hysteresis loops are found to be influenced by the factors such as capacitance nature, resistivity effects and leakage current of the compounds. Hence, the study on effect of trivalent non-magnetic ion substitution in a hard magnetic Dy3Fe5O12 system leads to interesting intrinsic magnetic and ferroelectric properties and found suitability for the fabrication of energy storage and optoelectronic devices.

Europium ions and silver nanoparticles co-doped magnesium-zinc-sulfophosphate glasses: Evaluation of ligand field and Judd-Ofelt parameters

This paper reports the ligand field and Judd-Ofelt analyses of europium ions (Eu3+) and silver nanoparticles (AgNPs) activated magnesium-zinc-sulfophosphate glasses. Such glasses of composition 63.5P2O5–20MgO–15ZnSO4–1.5Eu2O3–yAgNPs (y = 0.0, 0.1, 0.3, 0.5, 0.7, 0.9 and 1.1 g in excess) were prepared via melt quenching method and characterized by different analytical tools. The feasibility of achieving a novel glass based efficient red laser and light emitting diodes (LEDs) was explored. XRD analyses of as-quenched samples verified their glassy character. UV–Vis–NIR absorption spectra of the studied glasses displayed eight peaks at 360, 380, 394, 414, 465, 531, 2091 and 2205 nm allocated to the 7F0→5L6,7F0→5G4,7F1→5L6,7F1→5D3, 7F0→5D2,7F1→5D17F6→7F0 and 7F1→7F6 transitions in the Eu3+. Observed improvement in the photoluminescence intensity associated to 5D0→7F2 transition was majorly attributed to the energy transfer among Eu3+ and AgNPs enabled localised surface plasmon resonance induced local field effects. TEM analysis confirmed the uniform dispersion and nucleation of AgNPs (average diameter ≈27.65 nm) in the glass matrix. Judd-Ofelt analyses were performed to calculate the intensity parameters (Ω2, Ω4 and Ω6) and radiative properties wherein the experimental optical data were utilized. For the studied glasses, the disclosed trend of Ω2˃Ω4 validated their ionic character and high symmetry environment around Eu3+. Proposed glass composition revealed excellent values of optical gain 2.82×10−25cm2S−1 to 20.81×10−25cm2S−1 and branching ratio (4.33–75.8%). Optimum values of critical laser parameters for 5D0→7F2 transition in MZSPEAg1.1 g glass was 20.8 × 10−25 cm2 s−1 for the optical gain and 21.1×10−22cm2 for gain bandwidth. Furthermore, the Racah parameters calculated from the first three significant visible absorption bands were reduced from 82.85×cm−1 to 72.33×cm−1 with the increase in AgNPs contents (from 0.1 to 1.1 g), signifying the weakening in f-f electrons repulsion. It was asserted that the proposed glass composition may contribute towards the development of solid-state laser and LEDs.

Intense red and green luminescence from holmium activated zinc-sulfo-boro-phosphate glass: Judd-Ofelt evaluation

Rare-earth ions doped oxide glasses became prospective for high quality and inexpensive solid state laser development. To fulfill this need, zinc-sulfo-boro-phosphate glasses doped with holmium ions (Ho3+) were synthesized via melt-quenching method. Prepared glasses were characterized using diverse techniques to determine the influence of varied Ho3+ contents on their optical absorption and photoluminescence (PL) emission properties. The main purpose of this paper was to determine the structural and optical correlation in Ho3+ activated phosphate-based glass host involving the red and green lasing potency of holmium. Raman, XPS and FTIR spectra were recorded to analyze the structural properties of the synthesized glasses. Furthermore, Judd-Ofelt (J-O) intensity (Ωλ with λ = 2, 4 and 6) and radiative parameters were calculated. Absorption spectra of the studied glasses disclosed thirteen characteristic peaks associated to the transitions from the lowest electronic energy level (5I8) to various excited levels in Ho3+. The PL spectra of the proposed glasses revealed 3 significant peaks allocated to the 5F4 → 5I8, 5F5 → 5I8 and 5F4 → 5I7 transitions in Ho3+. Revelation of negative bonding parameter values implied the existence of ionic bond between the ligand and Ho3+ in the prepared glass host. Values of Ω2, Ω4 and Ω6 were observed in the range of (5.11–22.62)×10−20 cm2, (9.54–13.79)×10−20 cm2 and (3.71–6.78)×10−20 cm2, respectively. Lower Ω2 value signified the higher symmetry around Ho3+, whereas higher Ω4 and Ω6 values indicated the stronger rigidity of the glass network. The achieved large stimulated emission cross-section for the red and green spectral transitions from Ho3+ ((29.47–46.01)×10−21 cm2 for 5F4 → 5I8, (31.47–39.74)×10−21 cm2 for 5F5 → 5I8 and (13.34–31.63)×10−21 cm2 for 5F4 → 5I7) clearly displayed the lasing effectiveness of the proposed glasses.

Bandwidth enhancement of ∼3 μm emission and energy transfer mechanism in Yb3+/Ho3+/Dy3+ co-doped PbF2 crystal

The ∼3 μm emission in Yb3+/Ho3+/Dy3+ doped with PbF2 crystal is investigated in this paper. The involved energy transfer mechanisms between Yb3+/Ho3+/Dy3+ in PbF2 crystal is explained in detail. As far as we know, it is the first time to report a broadband emission extending from about 2600 to 3400 nm with a maximum full width at half maximum (FWHM) of 283 nm obtained in Yb0.02Ho0.02Dy0.02: Pb0.94F2 crystal under 970 nm pump. The energy transfer efficiency from Ho3+: 5I7 to Dy3+: 6H13/2 is as high as 97.9%, and the Ho3+: 5I6 → 5I7 fluorescence lifetime ratio τ(5I6)/τ(5I7) in the Yb0.02Ho0.02Dy0.02: Pb0.94F2 crystal was calculated to be 105.1%, indicating that Dy3+ ion is to be an efficient deactivated ion for Ho3+ ion to greatly facilitate the Ho3+: 5I6 → 5I7, while also broaden the mid-infrared lasers operating in the wavelength region ∼3 μm. All imply that Yb0.02Ho0.02Dy0.02: Pb0.94F2 crystal can be a potential candidate for the development of solid-state lasers operating in the mid-infrared broadband emission.

Visible light emission from Dy3+ doped tellurite glass: Role of silver and titania nanoparticles co-embedment

We report the influence of silver (Ag) and titania (TiO2) nanoparticles (ATNPs) co-embedment on the photoluminescence (PL) properties of dysprosium ions (Dy3+) doped zinc-magnesium tellurite glass system prepared using conventional melt quenching method. Both up- and down- converted PL spectra of glasses revealed three emission bands located at 482 (blue: 4F9/2 → 6H15/2), 574 (yellow: 4F9/2 → 6H13/2) and 664 nm (weak red: 4F9/2 → 6H11/2), where the band intensities were enhanced with the inclusion of ATNPs. Glasses with 0.2 mol% of ANPs and up to 0.3 mol% of TNPs disclosed highest PL intensity enhancement, which was majorly attributed to the ATNPs mediated localized surface plasmon resonance (LSPR) and large field enhancement (called hot spot) effects in the proximity of Dy3+ ions. Absorption spectra of glasses displayed two plasmon bands characteristics of each type of nanoparticle. It was inferred that the superposition of localized SP modes from ATNPs could generate new hybridized modes (strong local field in the vicinity of Dy3+ ions) shifted with respect to the single type of NPs resonance. HRTEM images showed the existence of both Ag and titania NPs inside the glass matrix. Glasses containing ATNPs exhibited anatase phase with (103) and (112) nanocrystalline lattice plane orientation. Proposed glass system may be useful for the development of solid state laser and photonic devices.

Spectroscopic properties of Dy3+ doped tellurite glass with Ag/TiO2 nanoparticles inclusion: Judd−Ofelt analysis

Silver (Ag) and Titania (TiO2) nanoparticles (ATNPs) co−embedded and dysprosium (Dy3+) ions doped magnesium−zinc−tellurite glasses were synthesized via melt quenching method. As−prepared samples were characterized using various analytical tools. Nanoparticles concentration dependent spectroscopic properties of the prepared glasses were evaluated using Judd−Ofelt (J−O) analysis. XRD pattern verified the amorphous nature of as−quenched samples. The UV–Vis spectra revealed six absorption bands centred at 1690, 1283, 1097, 904, 800 and 755 nm, assigned to the transitions from the ground level to different excited levels of Dy3+ ions. The photoluminescence (PL) emission spectra of the glass system displayed three emission bands positioned at 482 (blue: 4F9/2 → 6H15/2), 574 (yellow: 4F9/2 → 6H13/2) and 664 nm (weak red: 4F9/2 → 6H11/2). For all the bands, the PL intensities of the studied glasses were more pronounced than singly embedded sample (either ANPs or TNPs). Furthermore, the enhancement in the PL peak intensity due to the inclusion of metallic NPs was attributed to the surface plasmon resonance mediated local field effect in the proximity of Dy3+ ions. Ligand bonding of Dy3+ showed the ionic nature of the prepared glasses. The absorption and emission spectral data were used to evaluate the J−O intensity parameters (Ωλ (λ = 2, 4, 6)) and radiative properties. Values of Ωλ (λ = 2, 4, 6) for glass with 0.1 mol% of TNPs exhibited the trend of Ω2>Ω6>Ω4 while all other glasses revealed Ω2>Ω4>Ω6. It was demonstrated that by combining two types of NPs (Ag and TiO2) hot spot with intense electromagnetic field could be created in the neighbourhood of Dy3+ ion to achieve enhanced optical attributes of the proposed glasses. The attainment of large quality factors and quantum efficiency (≈100%) in the ATNPs co−embedded glasses were established to be beneficial for the development of solid state lasers and other photonic devices.

Finding the Next Deep-Ultraviolet Nonlinear Optical Material: NH4B4O6F.

Nonlinear optical materials are essential for the development of solid-state lasers. KBe2BO3F2 (KBBF) is a unique nonlinear optical material for generation of deep-ultraviolet coherent light; however, its industrial application is limited. Here, we report a new material NH4B4O6F, which exhibits a wide deep-ultraviolet transparent range and suitable birefringence that enables frequency doubling below 200 nm. NH4B4O6F possesses large nonlinear coefficients about 2.5 times that of KBBF. In addition, it is easy to grow bulk crystals and does not contain toxic elements.

SnO2 nanoparticles concentration dependent structural and luminescence characteristics of Er+ 3 doped zinc-lead-phosphate glass

We report the modifications in the structural and luminescence properties of erbium (Er+3) doped Zinc-Lead-Phosphate (ZLP) glasses containing SnO2 nanoparticles (SNPs). Glasses are prepared via melt quenching technique and characterized using high resolution scanning electron microscope (FE-SEM), differential thermal analyzer (DTA), Fourier transform infrared (FTIR), UV–Visible absorption and photoluminescence (PL) spectroscopy. The DTA results showed an enhancement in the thermal stability with the incorporation of SNPs. The FESEM micrograph revealed the occurrence of uniformly distributed SNPs with average diameter around 21nm. FTIR spectra exhibited various bonding vibrations, where the IR transmission band intensities are increased accompanied by a shift with the increase of SNPs contents. The UV–Vis spectra displayed six significant absorption peaks centered around 1536, 979, 799, 650, 523, and 485 nm. Room temperature PL spectra showed three emission peaks centered at 502, 545 and 606 nm. The emission intensities are enhanced with increasing SNPs contents. Present glass composition may be useful for the development of solid state lasers and other photonic devices.

Absorption Features and Luminescence Enhancement of Tellurite Glass Embedded with Metallic Nanoparticles

This presentation provides a panoramic overview of the recent progress in nanoglass plasmonics, challenges, excitement, applied interests and the future promises. Enhanced optical properties of rare earth (RE) doped glasses for sundry applications are current challenges in materials science and technology. Nanoparticles (NPs) dispersed up-converted (UC) glasses seem to be the ideal candidates in terms of both efficiency and large area coverage provided the absorption cross-section be enhanced. The glasses containing gold NPs (AuNPs) and silver NPs (AgNPs) doped with optimum concentration of RE ions are of particular interest to us. We report the influence of embedded NPs on the luminescence and absorbance characteristics of RE ions doped tellurite glass prepared by melt-quenching method. The absorption and emission spectra displays several prominent peaks corresponding to the transitions from the ground state to the excited states of RE ion. The observed efficient enhancement of up-conversion emissions and absorbance in the entire visible region is attributed to strong localized electric field in vicinity of NPs. Improvements of radiative emissions suggests that the proposed glasses are potential for the development of solid state lasers, color displays and nanophotonic devices.

Status of the High Average Power Diode-Pumped Solid State Laser Development at HiLASE

An overview of the latest developments of kilowatt-level diode pumped solid state lasers for advanced applications at the HiLASE Centre is presented. An overview of subcontracted and in-house-developed laser beamlines is presented. The aim of development is to build kW-class beamlines delivering picosecond pulses between 1- and 100-kHz repetition rates and high-energy nanosecond pulses at 10 Hz. The picosecond beamlines are based on Yb:YAG thin-disk amplifiers and chirped pulse amplification. The current status of the beamlines’ performance is reported. The advantages of zero-phonon line and pulsed pumping are demonstrated with respect to efficiency, thin disk temperature and beam quality. New diagnostics methods supporting the high average power lasers’ development, such as the high-resolution spectroscopy of Yb-doped materials, in situ thin disk deformation measurements, single-shot M2 measurement, realization of wavefront correction by a deformable mirror and the laser performance of a new mixed garnet ceramics, are described. The energetic, thermal and fluid-mechanical numerical modeling for the optimization of the multi-slab amplifiers is also described.

Spectroscopic investigation and Judd–Ofelt analysis of silver nanoparticles embedded Er3+-doped tellurite glass

A series of silver nanoparticles (NPs) embedded zinc-tellurite glass is prepared by melt-quenching technique. The transmission electron microscopic images reveal spherical as well as anisotropic silver NPs having average diameter in the range of 14–48 nm. The Er3+-free glass sample containing AgCl exhibits surface plasmon resonance (SPR) band of Ag NPs centered at ∼ 501 nm. From Judd–Ofelt analysis, it is found that by increasing the concentration of NPs, the value of Ω2 is enhanced suggesting increased covalency and decreased symmetry around the Er3+ ions. Integrated emission cross-section (IEC) is enhanced as the concentration of silver NPs is increased up to 0.5 mol% AgCl. Fourier infrared spectra show that the intensity of the vibrational band of the water molecule and fundamental stretching band of OH group are suppressed. Furthermore, under an excitation wavelength of 786 nm, three prominent upconversion emissions are observed at 520 nm, 550 nm and 650 nm which are attributed to 2H11/2 → 4I15/2, 4S3/2 → 4I15/2, and 4F9/2 → 4I15/2 transitions, respectively. The upconversion emissions are enhanced significantly by introduction of silver NPs. The enhancement is mainly attributed to the local field effect of silver NPs. Studied nanocomposites are potential candidates for the development of solid state lasers.

Influence of Europium Ion on Structural, Mechanical and Luminescence Behavior of Tellurite Nanoglass

Understanding the mechanism of enhanced luminescence of rare earth doped glasses in the presence of nanocrystallites and growth kineics is fundamentally important for optical devices. Tellurite nanoglasses of composition (80-x) TeO2 − 5 Na2O − 15 MgO − (x) Eu2O3, over the concentration region of 0 to 2.5 mol% are prepared using conventional melt-quenching technique. The nanocrystalline particles are obtained by heating the as-cast glass at temperature 15−20°C above the glass crystallization temperature (Tc). The sizes of nanocrystallites are estimated from the X-Ray Diffraction (XRD) pattern using the Scherrer equation having average diameter ∼68.7 nm. SEM studies revealed the nanocrystal glass morphology associated with the existence of crystalline phase. The glass density is determined by Precisa Densitometer and the hardness by the Vickers micro-hardness method. The density of tellurite nano-glass is found to be in the range of 5.2413 to 5.4933 g cm−3 while the Vickers microhardness varies from 2.77 to 2.93 GPa depending on the dopant concentration. The photoluminescence (PL) spectra exhibits five peaks around 568 nm, 600 nm, 628 nm, 664 nm and 712 nm assigned to 5D0 → 7F0, 5D0 → 7F1, 5D0 → 7F2, 5D0 → 7F3 and 5D0 → 7F4 transitions respectively. Interestingly, the FWHM and the inverse quality factor of the heat-treated glass are found to decrease with increasing concentration of Eu3+ dopants. Our observation may contribute towards the development of solid state lasers.

A critical study of the emergence of glass and glassy metals as “green” materials

In 2008, The National Academy of Engineering (NAE – Washington, DC) identified the glass family (glasses, glass ceramics and glass composites) as central to many of the great engineering achievements of the twentieth century: the development of solid state lasers and optical glass fibers, biomaterials, glasses for imaging technologies, and glass films in microelectronic devices.The work reported in this paper discusses the importance of glass and metallic glasses as environmental friendly materials and also provide some points of view about the future influence of these materials for the related fields of industrial engineering and industrial ecology. The environmental capabilities of metallic glasses (MGs), which are considered to be among the important materials of the future, have not been sufficiently investigated. However, some aspects have yet to be done: the biocompatibility of most MGs, obtaining valuable MGs from waste materials, using MGs in green energy applications (solar cells and hydrogen production), using MGs in catalyst systems, as well as the possibility for using MGs in systems for retention and purification of dangerous pollutants and in the nuclear industry.

Is this the time for a high-energy laser weapon program?

The U.S. Department of Defense (DoD) has made large investments weaponizing laser technology for air defense. Despite billions of dollars spent, there has not been a successful transition of a high-energy laser (HEL) weapon from the lab to the field. Is the dream of a low-cost-per-shot, deep-magazine, speed-of-light HEL weapon an impossible dream or a set of technologies that are ready to emerge on the modern battlefield? Because of the rapid revolution taking place in modern warfare that is making conventional defensive weapons very expensive relative to the offensive weapons systems, the pull for less expensive air defense may necessitate a HEL weapon system. Also, due to the recent technological developments in solid-state lasers (SSL), especially fiber lasers, used throughout manufacturing for cutting and welding, a HEL weapon finally may be able to meet all the requirements of ease of use, sustainability, and reliability. Due to changes in warfare and SSL technology advances, the era of HEL weapons isn't over; it may be just starting if DoD takes an evolutionary approach to fielding a HEL weapon. The U.S. Navy, with its large ships and their available electric power, should lead the way.

Enhanced Infrared to Visible Upconversion Emission in Er<sup>3+</sup> Doped Phosphate Glass Containing Silver Nanoparticles

Phosphate glasses containing fixed concentration of rare-earth with and without metallic nanoparticles (NPs) having compositions (59.5-x) P2O5-MgO-xAgCl-0.5Er2O3, where 0 ≤ x ≤ 1.5 mol% was prepared using melt-quenching technique. Spectral characterizations were made using UV-VIS-IR spectroscopy and photoluminescence spectroscopy. Addition of silver NPs enhanced the corresponding absorption and was optimum at 1.5 mol% AgCl. Infrared to visible frequency upconversion (UC) emission were observed in the glass on pumping with 797 nm radiation. Furthermore, it was found that the emission at 540 nm, due to Er3+transition (4S3/2-4I15/2) was much more influenced by the silver NPs in comparison to the emission at 632 nm (4F9/2 - 4I15/2). These enhancements were attributed to the local fields present in the vicinity of silver NPs. Moreover, the rapid increase in the intensity of the green band as compared to the red band was due to the charge cloud effect of the plasmon band. Since green band lie more close to the plasmon frequency band of Ag and hence showed rapid increase compared to the far lying red bands. Our findings may contribute towards the development of solid state laser and sensors

Er3+/Pr3+ co-doped fluorophoshate glass shows emission at 2.7 μm promising for solid-state laser development

Er³⁺/Pr³⁺ co-doped fluorophoshate glass shows emission at 2.7 μm promising for solid-state laser development