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20 pages, 3472 KB

Open AccessArticle

All-Chalcogenide High-NA Broadband Achromatic Metalens for Long-Wavelength Infrared Regime

by Minsi Lin, Zhenqi Huang, Yue Shen, Haobin Xiao, Yingying Fu, Mingjie Zhang, Yuanzhi Chen, Yi Zhou, Siqi Zhu and Zhenqiang Chen

Photonics 2026, 13(5), 433; https://doi.org/10.3390/photonics13050433 - 28 Apr 2026

Viewed by 422

Abstract

The long-wave infrared band, which at room temperature covers the infrared radiation of humans and objects, has significant applications across various fields including wireless communication, national defense, military, biomedical, and advanced driver assistance systems. Metalens provides a pathway to lightweight, compact, and integrated [...] Read more.

The long-wave infrared band, which at room temperature covers the infrared radiation of humans and objects, has significant applications across various fields including wireless communication, national defense, military, biomedical, and advanced driver assistance systems. Metalens provides a pathway to lightweight, compact, and integrated solutions for infrared imaging and sensing systems, marking an inevitable trend in future development. This study presents a design for a high numerical aperture of 0.89 in a polarization-insensitive all-chalcogenide metalens operating at 10 µm, utilizing the commercially available chalcogenide glass material As₂Se₃ via a transmission phase approach. Building upon this, we have achieved, for the first time, a high numerical aperture of 0.84 for an all-chalcogenide broadband LWIR achromatic metalens operating in the 9.5–10.5 µm range, with significantly improved focusing performance through the application of particle swarm optimization algorithms. The superior performance of the all-chalcogenide LWIR metalens, combined with the advantages of chalcogenide glass over traditional LWIR materials such as Si or Ge—namely, lower cost, reduced optical loss, and a smaller thermo-optic coefficient—suggests it has significant potential for broader applications. Full article

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10 pages, 3230 KB

Open AccessArticle

Terahertz Properties of GeAsSeSbSnTe Chalcogenide Glassy Semiconductors

by Alexander V. Andrianov, Alexey A. Shakhmin, Alexey G. Petrov, Nikolay V. Sivov and Grigory I. Kropotov

Micromachines 2026, 17(5), 533; https://doi.org/10.3390/mi17050533 - 27 Apr 2026

Viewed by 222

Abstract

Chalcogenide glasses are known as optical materials for the infrared spectral range. These compounds may also be of interest as materials for the low-frequency part of the terahertz range of electromagnetic waves, which is currently being intensively studied in connection with the numerous [...] Read more.

Chalcogenide glasses are known as optical materials for the infrared spectral range. These compounds may also be of interest as materials for the low-frequency part of the terahertz range of electromagnetic waves, which is currently being intensively studied in connection with the numerous possible applications of terahertz radiation. However, the terahertz optical characteristics of chalcogenide glasses remain poorly studied. In this work, eight different compositions of GeAsSeSbSnTe chalcogenide glasses were investigated using terahertz time-domain spectroscopy. A number of compositions, in particular GeSeTe and AsSeSbSn, were studied in the terahertz spectral range for the first time. Spectra of the refractive index and extinction coefficient were obtained for studied materials in the spectral range of 0.1–2.2 THz. The experimental frequency dependence of the product of the terahertz power absorption coefficient and the refractive index for the entire set of studied glasses is approximated by a power function. It was established that the exponent of the approximating power functions varies from 1.68 to 2.34 depending on the composition of the chalcogenide glass. For the studied glasses, a correlation was found between the values of the average coordination number characterizing the chalcogenide glass structure, and the values of the exponent of the functions approximating the THz absorption spectra. Full article

(This article belongs to the Special Issue Passive and Active THz Devices)

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15 pages, 4391 KB

Open AccessArticle

Secondary Imaging Architecture for Fast and Ultra-Wide LWIR Optics with Low Rectilinear Distortion

by Kuo-Chuan Wang and Cheng-Huan Chen

Sensors 2026, 26(8), 2334; https://doi.org/10.3390/s26082334 - 9 Apr 2026

Viewed by 351

Abstract

Wide-swath longwave infrared (LWIR) imaging from Low Earth Orbit (LEO) demands fast optics and rectilinear (F-tan) mapping for thermal mapping and multi-frame registration. Achieving an F/1.2 aperture with a 112° diagonal field of view (FOV) and distortion within ±5% is challenging, as mapping [...] Read more.

Wide-swath longwave infrared (LWIR) imaging from Low Earth Orbit (LEO) demands fast optics and rectilinear (F-tan) mapping for thermal mapping and multi-frame registration. Achieving an F/1.2 aperture with a 112° diagonal field of view (FOV) and distortion within ±5% is challenging, as mapping constraints and field-dominant off-axis aberrations become strongly coupled at large chief-ray angles. The low-distortion target is not only a geometric specification, but also a practical requirement that reduces peripheral compression, helps maintain edge-detail consistency, and lowers digital de-warping effort in the processing pipeline. While traditional LWIR secondary imaging is predominantly restricted to narrow-field cooled systems for cold-stop constraints, the proposed architecture utilizes a curved intermediate image to effectively decouple mapping formation in the field-dominant front objective from aperture-dominant correction in the rear group. Using chalcogenide glasses, the lens achieves a 5.7 mm effective focal length within a 186.9 mm total track. Analysis over the 8–12 μm band confirms performance approaching the diffraction limit at the 50 lp/mm Nyquist frequency alongside stable geometric fidelity across the full field. Thermal analysis from −40 °C to 80 °C and Monte Carlo tolerance analysis demonstrate stable imaging performance and manufacturing feasibility, confirming the effectiveness of the proposed design approach. Full article

(This article belongs to the Special Issue Remote Sensing Image Processing, Analysis and Application)

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36 pages, 6481 KB

Open AccessReview

Advances in Photonic Gas Sensors Operating in the VIS–NIR Spectrum: Structures, Materials, and Performance

by Nourhan Rasheed, Xun Li and Mohamed Bakr

Sensors 2026, 26(5), 1568; https://doi.org/10.3390/s26051568 - 2 Mar 2026

Cited by 1 | Viewed by 970

Abstract

The growing need for real-time, accurate monitoring of hazardous gases in environmental, industrial, and healthcare settings has highlighted the limitations of traditional sensing methods. Photonic Integrated Circuits (PICs) have become a revolutionary platform due to their high sensitivity, accurate selectivity, compact size and [...] Read more.

The growing need for real-time, accurate monitoring of hazardous gases in environmental, industrial, and healthcare settings has highlighted the limitations of traditional sensing methods. Photonic Integrated Circuits (PICs) have become a revolutionary platform due to their high sensitivity, accurate selectivity, compact size and cost-effectiveness. We present in this work a comprehensive overview of the best-reported PIC-based gas sensors. We discuss the basic concepts behind resonance-based and absorption-based sensing. A detailed overview of the various material platforms, from well-known silicon and silicon nitride to new polymers, chalcogenide glasses, and 2D materials, is presented. A comparison of key device topologies, such as waveguides, microring resonators, Mach–Zehnder interferometers, and metasurfaces, is conducted, with performance benchmarks indicating the limit of detection (LoD). The main limitations of PIC sensors are discussed in this review. We also discuss promising technologies, especially the game-changing potential of artificial intelligence to create fully autonomous devices. Full article

(This article belongs to the Special Issue Optical Sensors for Industry Applications)

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16 pages, 3113 KB

Open AccessArticle

Relationship of Metallophilic Interactions with Structural and Mechanical Properties of (1−x) (0.73GeSe₂-0.27Sb₂Se₃)-xAg₂Se Glasses

by Yuriy S. Tveryanovich, Andrey S. Tverjanovich, Vladimir V. Tomaev, Anton S. Mazur, Svyatoslav S. Lun’kov, Sonya A. Zaytseva and Eugene Bychkov

Compounds 2025, 5(4), 56; https://doi.org/10.3390/compounds5040056 - 8 Dec 2025

Viewed by 744

Abstract

The effect of Ag₂Se content on the structure and mechanical properties of (1−x) (0.73GeSe₂-0.27Sb₂Se₃)-xAg₂Se glasses is analyzed. The glass structure is studied using XRD and NMR analyses. A particular [...] Read more.

The effect of Ag₂Se content on the structure and mechanical properties of (1−x) (0.73GeSe₂-0.27Sb₂Se₃)-xAg₂Se glasses is analyzed. The glass structure is studied using XRD and NMR analyses. A particular consideration relates to a multiple increase in plasticity with increasing silver selenide content in chalcogenide glasses. The observed effects are attributed to the formation of silver–silver metallophilic interactions. Full article

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16 pages, 2519 KB

Open AccessReview

Glass Formation in the GeSe₂–As₂Se₃–MeCh Systems (Me = Cu, Ag, Zn, Cd, Sn, Pb; Ch = S, Se, Te)

by Lilia Aljihmani

Materials 2025, 18(21), 5058; https://doi.org/10.3390/ma18215058 - 6 Nov 2025

Viewed by 814

Abstract

The creation of novel, effective materials with specific properties is necessary to advance technology. To do this, objective regularities between the material’s composition, structure, and properties must be found. A comparative analysis of glass-forming regions, arranged according to the systematic substitution of one [...] Read more.

The creation of novel, effective materials with specific properties is necessary to advance technology. To do this, objective regularities between the material’s composition, structure, and properties must be found. A comparative analysis of glass-forming regions, arranged according to the systematic substitution of one element by its analog within a periodic system subgroup, provides a useful framework for discussing trends in glass formation in semiconductor alloys. In this review, the information on the glass formation in the chalcogenide systems GeSe₂–As₂Se₃–MeCh, where Me = Cu, Ag, Zn, Cd, Sn, Pb; Ch = Se, Te, was subjected to a thorough comparative analysis to establish objective patterns in the change in the glass-forming ability in these systems. The effect of MeCh on the formation of glass in the binary system GeSe₂–As₂Se₃ was traced. Full article

(This article belongs to the Section Advanced and Functional Ceramics and Glasses)

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19 pages, 2667 KB

Open AccessArticle

Theoretical Aspects of Topology and Successful Applications to Glasses and Proteins

by Punit Boolchand, James Charles Phillips, Matthieu Micoulaut and Aaron Welton

Int. J. Topol. 2025, 2(3), 14; https://doi.org/10.3390/ijt2030014 - 9 Sep 2025

Viewed by 1568

Abstract

The origin of glass formation has been one of the greatest mysteries of science. The first clues emerged in Ge_xSe_1-x glasses, where the bond-stretching and bond angle-bending constraints are countable, and it was found that the most favorable compositions for [...] Read more.

The origin of glass formation has been one of the greatest mysteries of science. The first clues emerged in Ge_xSe_1-x glasses, where the bond-stretching and bond angle-bending constraints are countable, and it was found that the most favorable compositions for glass formation involved matching constraints with the degrees of freedom. Modulated-Differential Scanning Calorimetric (MDSC) studies on Ge_xSe_1-x chalcogenide glasses revealed two elastic phase transitions—a stiffness transition at x = 0.20 and a stress transition at x = 0.26—leading to the observation of three topological phases: a flexible phase at x < 0.20, an intermediate phase in the 0.20 < x < 0.26 range, and a stressed–rigid phase for compositions x > 0.26. The three topological phases (TPs) have now been generically observed in more than two dozen chalcogenides and modified oxide glasses. In proteins, the transition from the unfolded (flexible) to the folded (isostatically rigid intermediate) phase represents the stiffness transition. Self-organization causes proteins to display a dynamic reversibility of the folding process. The evolutions of protein dynamics may also exhibit stiffness phase transitions similar to those seen in glasses. Full article

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11 pages, 3403 KB

Open AccessArticle

Optical Design and Lens Fabrication for Automotive Thermal Imaging Using Chalcogenide Glass

by Young-Soo Choi and Ji-Kwan Kim

Micromachines 2025, 16(8), 901; https://doi.org/10.3390/mi16080901 - 31 Jul 2025

Viewed by 1912

Abstract

This paper is about the design and fabrication of infrared lenses, which are the core components of thermal imaging cameras to be mounted on vehicles. To produce an athermalized optical system, chalcogenide glass (As₄₀Se₆₀) with a lower thermo-optic coefficient [...] Read more.

This paper is about the design and fabrication of infrared lenses, which are the core components of thermal imaging cameras to be mounted on vehicles. To produce an athermalized optical system, chalcogenide glass (As₄₀Se₆₀) with a lower thermo-optic coefficient (dn/dT) than germanium was adopted as a lens material, and each lens was designed so that defocus occurs in opposite directions depending on temperature. The designed lens was fabricated using a compression molding method, and the molded lenses showed less than 1.5 μm of form error (PV) using a mold iteration process. Through evaluations of MTF and thermal images obtained from the lens module, it was judged that this optical design process is obtainable. Full article

(This article belongs to the Collection Optical MEMS: Design, Fabrication, Control, Modeling and Developments)

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13 pages, 3594 KB

Open AccessArticle

The Synthesis of New Chalcogenides from the System GeTe₆-Cu and a Layered Structure Based on Them and an Azo Polymer for Application in Optoelectronics

by Yordanka Trifonova, Ani Stoilova, Deyan Dimov, Georgi Mateev, Dimana Nazarova, Lian Nedelchev, Vladislava Ivanova and Vanya Lilova

Materials 2025, 18(14), 3387; https://doi.org/10.3390/ma18143387 - 18 Jul 2025

Viewed by 885

Abstract

New bulk chalcogenides from the system (GeTe₆)_1−xCu_x, where x = 5, 10, 15 and 20 mol%, have been synthesized. The structure and composition of the materials were studied using X-ray powder diffraction (XRD) and energy-dispersive spectroscopy (EDS). [...] Read more.

New bulk chalcogenides from the system (GeTe₆)_1−xCu_x, where x = 5, 10, 15 and 20 mol%, have been synthesized. The structure and composition of the materials were studied using X-ray powder diffraction (XRD) and energy-dispersive spectroscopy (EDS). Scanning electron microscopy (SEM) was applied to analyze the surface morphology of the samples. Some thermal characteristics such as the glass transition, crystallization and melting temperature and some physico-chemical properties such as the density, compactness and molar and free volumes were also determined. The XRD patterns show sharp diffraction peaks, indicating that the synthesized new bulk materials are crystalline. The following four crystal phases were determined: Te, Cu, CuTe and Cu₂GeTe₃. The results from the EDS confirmed the presence of Ge, Te and Cu in the bulk samples in concentrations in good correspondence with those theoretically determined. A layered thin-film material based on Ge₁₄Te₈₁Cu₅, which exhibits lower network compactness compared to the other synthesized new chalcogenides, and the azo polymer PAZO was fabricated, and the kinetics of the photoinduced birefringence at 444 nm was measured. The results indicated an increase in the maximal induced birefringence for the layered structure in comparison to the non-doped azo polymer film. Full article

(This article belongs to the Special Issue New Generation Materials for Advanced Electronic and Biomedical Applications)

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14 pages, 2175 KB

Open AccessArticle

Engineering Ultra-Low Thermal Conductivity in (Pb_0.8Ge_0.2Te)_0.95-x(PbSe)_0.05(PbS)_x Quaternary Lead Chalcogenides Through PbS-Induced Phase Segregation

by Dianta Ginting, Hadi Pronoto, Nurato, Kontan Tarigan, Sagir Alva, Muhamad Fitri, Dwi Nanto, Ai Nurlaela, Mashadi, Yunasfi, Toto Sudiro, Jumril Yunas and Jong-Soo Rhyee

Materials 2025, 18(14), 3232; https://doi.org/10.3390/ma18143232 - 9 Jul 2025

Cited by 1 | Viewed by 1217

Abstract

The shortage of tellurium and toxicity of lead are major obstacles to scaling mid-temperature thermoelectric generators. We engineer quaternary lead chalcogenides with composition (Pb_0.8Ge_0.2Te)_0.95-_x(PbSe)_0.05(PbS)_x (0 ≤ x ≤ 0.25), where Pb is lead, [...] Read more.

The shortage of tellurium and toxicity of lead are major obstacles to scaling mid-temperature thermoelectric generators. We engineer quaternary lead chalcogenides with composition (Pb_0.8Ge_0.2Te)_0.95-_x(PbSe)_0.05(PbS)_x (0 ≤ x ≤ 0.25), where Pb is lead, Ge is germanium, Te is tellurium, Se is selenium, S is sulfur, and x denotes the molar fraction of lead sulfide (PbS). The primary novelty lies in achieving ultra-low thermal conductivity through controlled phase segregation induced by systematic PbS incorporation. X-ray diffraction analysis reveals single-phase solid solutions up to x ≈ 0.10, with secondary PbS precipitates forming beyond this threshold. These PbS-rich phases create hierarchical microstructures that scatter phonons across multiple length scales, suppressing total thermal conductivity to 0.6 Wm⁻¹K⁻¹ at x = 0.15—approximately 84% lower than pristine lead telluride (PbTe) and approaching glass-like thermal conductivity values. Electrical transport measurements demonstrate sulfur’s role as an electron donor, enabling carrier-type control from p-type to n-type conduction. Despite moderate electrical power factors, the optimized composition (x = 0.20) achieves a peak dimensionless figure of merit ZT ≈ 0.34 at 650 K. This work demonstrates an effective strategy for tellurium-lean, lead-reduced thermoelectric materials through sulfur-induced phase segregation, providing practical design guidelines for sustainable waste heat recovery applications. Full article

(This article belongs to the Section Energy Materials)

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12 pages, 2833 KB

Open AccessArticle

Glass Transition Temperature and Mean Bond Energy of Chalcogenide Glasses in the As₂Se₃-GeTe-CdTe System

by Ina Karadashka, Petya Romanova and Veronika Karadjova

Inorganics 2025, 13(5), 160; https://doi.org/10.3390/inorganics13050160 - 9 May 2025

Cited by 1 | Viewed by 2234

Abstract

Chalcogenide samples from the As₂Se₃-GeTe-CdTe system were synthesized by the melt-quench technique. The surface topography of some of the samples was performed with the help of scanning electron microscopy. Various physical parameters of the chalcogenide glasses were calculated: the [...] Read more.

Chalcogenide samples from the As₂Se₃-GeTe-CdTe system were synthesized by the melt-quench technique. The surface topography of some of the samples was performed with the help of scanning electron microscopy. Various physical parameters of the chalcogenide glasses were calculated: the degree of cross-linking atom, the average heteropolar bond energy of the glasses, the content of chalcogen in the glass, the mean coordination number, and the average energy of the chemical bonds between the atoms of the metals in the glass. With their help, the components of the overall bond energy were calculated: the mean bond energy of the average cross-linking per atom and the average bond energy per atom of the “remaining matrix”. A linear dependence has been established between the glass transition temperature and the overall mean bond energy and between the glass transition temperature and the mean coordination number. The correlation between microhardness and glass transition temperature of chalcogenide glasses was investigated. The dependance between the composition and physical parameters of the As₂Se₃-GeTe-CdTe glasses was established and discussed. Full article

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16 pages, 2510 KB

Open AccessArticle

Ensemble Machine Learning for the Prediction and Understanding of the Refractive Index in Chalcogenide Glasses

by Miruna-Ioana Belciu and Alin Velea

Molecules 2025, 30(8), 1745; https://doi.org/10.3390/molecules30081745 - 14 Apr 2025

Cited by 2 | Viewed by 1484

Abstract

Chalcogenide glasses (ChGs) are a class of amorphous materials presenting remarkable mechanical, optical, and electrical properties, making them promising candidates for advanced photonic and optoelectronic applications. With the increasing integration of artificial intelligence in modern materials design, we are able to systematically select, [...] Read more.

Chalcogenide glasses (ChGs) are a class of amorphous materials presenting remarkable mechanical, optical, and electrical properties, making them promising candidates for advanced photonic and optoelectronic applications. With the increasing integration of artificial intelligence in modern materials design, we are able to systematically select, prepare, and optimize appropriate compositions for desired applications in a manner that was unachievable before. This study employs various machine learning models to reliably predict the refractive index at 20 °C using a small dataset of 541 samples extracted from the SciGlass database. The input for the algorithms consists of a selected set of physico-chemical features computed for the chemical composition of each entry. Additionally, these algorithms served as inner models for an ensemble logistic regression estimator that achieved a superior

R^{2}

value of 0.8985. SHAP feature analysis of the second-best model, CatBoostRegressor (

R^{2}

= 0.8920), revealed the importance of elemental density, atomic weight, ground state atomic gap, and fraction of p valence electrons in tuning the value of the refractive index of a chalcogenide compound. Full article

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6 pages, 1660 KB

Open AccessProceeding Paper

Chromatic Dispersion of Chalcogenide Glass-Based Photonic Crystal Fiber with Ultra-High Numerical Aperture

by Jyoti Chauhan, Yogita Kalra and Ravindra Kumar Sinha

Phys. Sci. Forum 2024, 10(1), 8; https://doi.org/10.3390/psf2024010008 - 20 Feb 2025

Cited by 2 | Viewed by 1035

Abstract

We report a graded index chalcogenide glass (As₂Se₃)-based photonic crystal fiber having a solid core. The proposed PCF has ultra-high numerical aperture value reaching up to 1.82 for the explored wavelength range of 1.8–10 μm in the mid-infrared region. [...] Read more.

We report a graded index chalcogenide glass (As₂Se₃)-based photonic crystal fiber having a solid core. The proposed PCF has ultra-high numerical aperture value reaching up to 1.82 for the explored wavelength range of 1.8–10 μm in the mid-infrared region. The value of numerical aperture increases as the pitch increase from 0.92 to 0.96 to 1 micrometer, at a particular value of wavelength. With this high value of numerical aperture, a PCF is capable of gathering a high amount of light in its core. With negative dispersion reaching up to −2000 ps/km/nm at 4.8 µm, the fiber acts as a dispersion-compensating fiber, with confinement loss being close to zero for higher values of wavelength. The confinement loss of the designed PCF is also significantly less and it decreases as the wavelength increases. Also, the value of dispersion is significantly less due to the regular variation in the size of the holes in the transverse direction, as compared to the design when there is no gradation. The design has been optimized with an appropriate value of the perfectly matched layer to achieve the best results. Full article

(This article belongs to the Proceedings of The 1st International Online Conference on Photonics)

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15 pages, 24395 KB

Open AccessArticle

Experimental Study on Shear Thickening Polishing of ZnS Glass

by Xueliang Zhang, Mingfeng Ke, Yuyang Chen, Lanying Shao, Jiahuan Wang, Julong Yuan and Binghai Lyu

Coatings 2025, 15(2), 184; https://doi.org/10.3390/coatings15020184 - 6 Feb 2025

Cited by 3 | Viewed by 2012

Abstract

Zinc sulfide (ZnS) is extensively utilized in various applications due to its exceptional optical transmittance across numerous spectral bands. To achieve ultra-high surface quality ZnS optical components, shear thickening polishing (STP) is employed to reduce roughness. A comparison between traditional fixed abrasive polishing [...] Read more.

Zinc sulfide (ZnS) is extensively utilized in various applications due to its exceptional optical transmittance across numerous spectral bands. To achieve ultra-high surface quality ZnS optical components, shear thickening polishing (STP) is employed to reduce roughness. A comparison between traditional fixed abrasive polishing (FAP) and STP for ZnS glass showed that FAP results in poor surface quality due to its low removal efficiency and uneven abrasive exposure, while STP provides better surface quality due to its flexible removal process, proving its feasibility and advancement. The Taguchi method was used to study the impact of three key polishing parameters on surface roughness (Ra) and the material removal rate (MRR), finding that polishing angle most influenced roughness and speed most influenced MRR. With optimal parameters, ZnS glass surface roughness was reduced from 110 ± 15 nm to 8.85 ± 0.5 nm, with an MRR of 32.5 nm/min. Scanning electron microscope (SEM) images further confirmed STP’s effectiveness in removing microdefects and smoothing the ZnS glass surface, offering a new method for the efficient, high-quality polishing of chalcogenide glasses without surface damage. Full article

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11 pages, 511 KB

Open AccessArticle

Exploring Structural Changes in Ge-Te Amorphous Films Through Small-Angle Neutron Scattering

by Andrea A. Piarristeguy, Raphaël Escalier, Annie Pradel, Viviana Cristiglio and Gabriel J. Cuello

Appl. Sci. 2024, 14(24), 11713; https://doi.org/10.3390/app142411713 - 16 Dec 2024

Viewed by 1287

Abstract

The structure of the glassy Ge_xTe_1−x system, with x = 0.17, 0.21, 0.28, 0.30, and 0.45, is studied using the small-angle neutron scattering (SANS) technique. The very-low-momentum-transfer region of the diffractogram exhibits distinct behaviour depending on the germanium content. [...] Read more.

The structure of the glassy Ge_xTe_1−x system, with x = 0.17, 0.21, 0.28, 0.30, and 0.45, is studied using the small-angle neutron scattering (SANS) technique. The very-low-momentum-transfer region of the diffractogram exhibits distinct behaviour depending on the germanium content. A similar conclusion is drawn from the analysis of the first diffraction peaks observed at higher angles. This system exhibits three composition regions with distinct behaviours: a first zone of low Ge content (up to about 20–25 at.%), a third zone richer in Ge (from about 30 at.% and above), and a second transitional zone between them. These changes are reflected in the parameters that govern Porod’s region, as well as in the region where the first diffraction peaks appear, corroborating previous observations made using other experimental and simulation techniques. Our study provides experimental evidence that could open up new possibilities for conducting simulations using neutron data. The results presented here show that increasing Ge content leads to a strengthening of the intermediate-range order at the expense of a weakening of the short-range order. Full article

(This article belongs to the Special Issue Advanced Research on Structure, Properties, and Applications of Glass Materials)

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