1
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Ryu CW, Egami T. Origin of liquid fragility. Phys Rev E 2020; 102:042615. [PMID: 33212574 DOI: 10.1103/physreve.102.042615] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 10/12/2020] [Indexed: 11/07/2022]
Abstract
Liquid fragility characterizes how steeply the viscosity of a glass-forming liquid decreases with increasing temperature above the glass transition. It is one of the most fundamental properties of a liquid, with high importance for science and application. Yet, its origin is unclear. Here we show that it is directly related to the structural coherence of the medium-range order (MRO) in liquid defined by the decay of the pair-distribution function with distance. The MRO can also be evaluated from the first peak of the structure function determined by x-ray or neutron diffraction, and it is a measure of the cooperativity of atomic motion in a diffusive event in supercooled liquids. These findings shed light on the mechanism of atomic transport in supercooled liquids.
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Affiliation(s)
- Chae Woo Ryu
- Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - Takeshi Egami
- Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee 37996, USA.,Materials Sciences and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.,Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
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2
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Song W, Li X, Wang M, Bauchy M, Micoulaut M. Dynamic and stress signatures of the rigid intermediate phase in glass-forming liquids. J Chem Phys 2020; 152:221101. [PMID: 32534532 DOI: 10.1063/5.0007093] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
We study the evolution of enthalpic changes across the glass transition of model sodium silicate glasses (Na2O)x(SiO2)100-x, focusing on the detection of a flexible-rigid transition and a possible reversibility window in relationship with dynamic properties. We show that the hysteresis resulting from enthalpic relaxation during a numerical cooling-heating cycle is minimized for 12% ≤ x ≤ 20% Na2O, which echoes with the experimental observation. The key result is the identification of the physical features driving this anomalous behavior. The intermediate-flexible boundary is associated with a dynamic onset with increasing depolymerization that enhances the growing atomic motion with a reduced internal stress, whereas the intermediate-stressed rigid boundary exhibits a substantial increase in the temperature at which the relaxation is maximum. These results suggest an essentially dynamic origin for the intermediate phase observed in network glass-forming liquids.
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Affiliation(s)
- W Song
- Physics of AmoRphous and Inorganic Solids Laboratory (PARISlab), Department of Civil and Environmental Engineering, University of California, Los Angeles, California 90095, USA
| | - X Li
- Physics of AmoRphous and Inorganic Solids Laboratory (PARISlab), Department of Civil and Environmental Engineering, University of California, Los Angeles, California 90095, USA
| | - M Wang
- Physics of AmoRphous and Inorganic Solids Laboratory (PARISlab), Department of Civil and Environmental Engineering, University of California, Los Angeles, California 90095, USA
| | - M Bauchy
- Physics of AmoRphous and Inorganic Solids Laboratory (PARISlab), Department of Civil and Environmental Engineering, University of California, Los Angeles, California 90095, USA
| | - M Micoulaut
- Sorbonne Université, Laboratoire de Physique Théorique de la Matière Condensée, 4 Place Jussieu, F-75252 Paris Cedex 05, France
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3
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Zheng Q, Zhang Y, Montazerian M, Gulbiten O, Mauro JC, Zanotto ED, Yue Y. Understanding Glass through Differential Scanning Calorimetry. Chem Rev 2019; 119:7848-7939. [DOI: 10.1021/acs.chemrev.8b00510] [Citation(s) in RCA: 154] [Impact Index Per Article: 30.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Qiuju Zheng
- School of Materials Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China
| | - Yanfei Zhang
- School of Materials Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China
| | - Maziar Montazerian
- Vitreous Materials Laboratory (LaMaV), Department of Materials Engineering (DEMa), Federal University of São Carlos (UFSCar), 13.565-905 São Carlos, SP, Brazil
| | - Ozgur Gulbiten
- Science and Technology Division, Corning Incorporated, Corning, New York 14831, United States
| | - John C. Mauro
- School of Materials Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Edgar D. Zanotto
- Vitreous Materials Laboratory (LaMaV), Department of Materials Engineering (DEMa), Federal University of São Carlos (UFSCar), 13.565-905 São Carlos, SP, Brazil
| | - Yuanzheng Yue
- School of Materials Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China
- State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan 430070, China
- Department of Chemistry and Bioscience, Aalborg University, DK-9220 Aalborg, Denmark
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Lucas P, Coleman GJ, Sen S, Cui S, Guimond Y, Calvez L, Boussard-Pledel C, Bureau B, Troles J. Structural and chemical homogeneity of chalcogenide glass prepared by melt-rocking. J Chem Phys 2019; 150:014505. [PMID: 30621415 DOI: 10.1063/1.5054704] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The chemical and structural homogeneity of selenide glasses produced by mechanical homogenization of the melt in a rocking furnace is investigated by Raman and Energy Dispersive Spectroscopy (EDS). Both techniques demonstrate that the glass is macroscopically homogeneous along the entire length of a 6 cm rod. EDS imaging performed over four orders of magnitude in scale further confirms that the glass is homogeneous down to the sub-micron scale. An estimate of the diffusion coefficient from experimental viscosity data shows that the diffusion length is far larger than the resolution of EDS and therefore confirms that the glass is homogeneous at any length scale. In order to investigate a systematic mismatch in physical properties reported in the literature for glasses produced by extended static homogenization, two germanium selenide samples are produced under the same conditions except for the homogenization step: one in a rocking furnace for 10 h and the other in a static furnace for 192 h. No difference in physical properties is found between the two glasses. The properties of an ultra-high purity glass are also found to be identical. The origin of the systematic deviation reported in the literature for germanium selenide glasses is therefore still unknown, but the present results demonstrate that homogeneity or dryness does not have a significant contribution in contrast to previous suggestions. The implications of glass homogeneity for technological applications and industrial production are discussed.
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Affiliation(s)
- Pierre Lucas
- Department of Materials Science and Engineering, University of Arizona, Tucson, Arizona 85721, USA
| | - Garrett J Coleman
- Department of Materials Science and Engineering, University of Arizona, Tucson, Arizona 85721, USA
| | - Sabyasachi Sen
- Division of Materials Science, University of California, Davis, California 95616, USA
| | - Shuo Cui
- Department of Materials Science and Engineering, University of Arizona, Tucson, Arizona 85721, USA
| | - Yann Guimond
- Umicore IR Glass, ZA du Boulais, Acigne 35960, France
| | - Laurent Calvez
- Univ Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes)-UMR 6226, F-35000 Rennes, France
| | - Catherine Boussard-Pledel
- Univ Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes)-UMR 6226, F-35000 Rennes, France
| | - Bruno Bureau
- Univ Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes)-UMR 6226, F-35000 Rennes, France
| | - Johann Troles
- Univ Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes)-UMR 6226, F-35000 Rennes, France
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5
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Yildirim C, Raty JY, Micoulaut M. Decoding entangled transitions: Polyamorphism and stressed rigidity. J Chem Phys 2018; 148:244505. [DOI: 10.1063/1.5034500] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Affiliation(s)
- Can Yildirim
- Laboratoire de Physique Théorique de la Matière Condensée, Sorbonne Université, 4 Place Jussieu, 75252 Paris Cedex 05, France
- Physique de la Matière Condensée, B5, Université de Liège, B4000 Sart-Tilman, Belgium
- European Synchrotron Radiation Facility, 71, Avenue des Martyrs, CS 40220, 38043 Grenoble Cedex 9, France
| | - Jean-Yves Raty
- Physique de la Matière Condensée, B5, Université de Liège, B4000 Sart-Tilman, Belgium
| | - Matthieu Micoulaut
- Laboratoire de Physique Théorique de la Matière Condensée, Sorbonne Université, 4 Place Jussieu, 75252 Paris Cedex 05, France
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6
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Dash S, Chen P, Boolchand P. Molecular origin of aging of pure Se glass: Growth of inter-chain structural correlations, network compaction, and partial ordering. J Chem Phys 2017; 146:224506. [DOI: 10.1063/1.4983480] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- S. Dash
- Department of Electrical Engineering and Computing Systems, Solid State Physics and Electronic Materials Laboratory, University of Cincinnati, Cincinnati, Ohio 45221, USA
| | - P. Chen
- Department of Electrical Engineering and Computing Systems, Solid State Physics and Electronic Materials Laboratory, University of Cincinnati, Cincinnati, Ohio 45221, USA
| | - P. Boolchand
- Department of Electrical Engineering and Computing Systems, Solid State Physics and Electronic Materials Laboratory, University of Cincinnati, Cincinnati, Ohio 45221, USA
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Li P, Zhang Y, Chen Z, Gao P, Wu T, Wang LM. Relaxation dynamics in the strong chalcogenide glass-former of Ge 22Se 78. Sci Rep 2017; 7:40547. [PMID: 28094287 PMCID: PMC5240093 DOI: 10.1038/srep40547] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 12/07/2016] [Indexed: 01/18/2023] Open
Abstract
The enthalpy relaxation is performed in the glassy Ge22Se78 to understand the dynamic behaviors. The structure of the glass is examined by X-ray diffraction and Raman spectra. The dynamic parameters such as the fragility, stretching exponent and non-linear factor are determined. A low fragility of m = 27 is exhibited for the chalcogenide, however, the stretching exponent is found not to have a larger value. The enthalpy relaxation spectra are constructed for various glass formers, and a relationship between the fragility and the symmetry of the spectra is demonstrated. The dynamic results are used to evaluate the structure of the Ge22Se78 glass.
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Affiliation(s)
- Pengfei Li
- State Key Lab of Metastable Materials Science and Technology, and College of Materials Science and Engineering, Yanshan University, Qinhuangdao, Hebei, 066004, China
| | - Yaqi Zhang
- State Key Lab of Metastable Materials Science and Technology, and College of Materials Science and Engineering, Yanshan University, Qinhuangdao, Hebei, 066004, China
| | - Zeming Chen
- State Key Lab of Metastable Materials Science and Technology, and College of Materials Science and Engineering, Yanshan University, Qinhuangdao, Hebei, 066004, China
| | - Peng Gao
- State Key Lab of Metastable Materials Science and Technology, and College of Materials Science and Engineering, Yanshan University, Qinhuangdao, Hebei, 066004, China
| | - Tao Wu
- State Key Lab of Metastable Materials Science and Technology, and College of Materials Science and Engineering, Yanshan University, Qinhuangdao, Hebei, 066004, China
| | - Li-Min Wang
- State Key Lab of Metastable Materials Science and Technology, and College of Materials Science and Engineering, Yanshan University, Qinhuangdao, Hebei, 066004, China
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Yildirim C, Raty JY, Micoulaut M. Anomalous diffusion and non-monotonic relaxation processes in Ge-Se liquids. J Chem Phys 2016; 144:224503. [PMID: 27306014 DOI: 10.1063/1.4953077] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We investigate the dynamical properties of liquid GexSe100-x as a function of Ge content by first-principles molecular dynamic simulations for a certain number of temperatures in the liquid state. The focus is set on ten compositions (where x ≤ 33%) encompassing the reported flexible to rigid and rigid to stressed-rigid transitions. We examine diffusion coefficients, diffusion activation energies, glassy relaxation behavior, and viscosity of these liquids from Van Hove correlation and intermediate scattering functions. At fixed temperature, all properties/functions exhibit an anomalous behavior with Ge content in the region 18%-22%, and provide a direct and quantitative link to the network rigidity.
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Affiliation(s)
- Can Yildirim
- Laboratoire de Physique Théorique de la Matière Condensée, Paris Sorbonne Universités, UPMC, 4, Place Jussieu, 75252 Paris Cedex 05, France
| | - Jean-Yves Raty
- Physique des Solides, Interfaces et Nanostructures et SESAME, B5 Université de Liège, B4000 Sart-Tilman, Belgium
| | - Matthieu Micoulaut
- Laboratoire de Physique Théorique de la Matière Condensée, Paris Sorbonne Universités, UPMC, 4, Place Jussieu, 75252 Paris Cedex 05, France
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Micoulaut M. Relaxation and physical aging in network glasses: a review. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2016; 79:066504. [PMID: 27213928 DOI: 10.1088/0034-4885/79/6/066504] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Recent progress in the description of glassy relaxation and aging are reviewed for the wide class of network-forming materials such as GeO2, Ge x Se1-x , silicates (SiO2-Na2O) or borates (B2O3-Li2O), all of which have an important usefulness in domestic, geological or optoelectronic applications. A brief introduction of the glass transition phenomenology is given, together with the salient features that are revealed both from theory and experiments. Standard experimental methods used for the characterization of the slowing down of the dynamics are reviewed. We then discuss the important role played by aspects of network topology and rigidity for the understanding of the relaxation of the glass transition, while also permitting analytical predictions of glass properties from simple and insightful models based on the network structure. We also emphasize the great utility of computer simulations which probe the dynamics at the molecular level, and permit the calculation of various structure-related functions in connection with glassy relaxation and the physics of aging which reveal the non-equilibrium nature of glasses. We discuss the notion of spatial variations of structure which leads to the concept of 'dynamic heterogeneities', and recent results in relation to this important topic for network glasses are also reviewed.
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Affiliation(s)
- Matthieu Micoulaut
- Paris Sorbonne Universités, LPTMC-UPMC, 4 place Jussieu, 75252 Paris cedex 05, France
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10
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Yildirim C, Raty JY, Micoulaut M. Revealing the role of molecular rigidity on the fragility evolution of glass-forming liquids. Nat Commun 2016; 7:11086. [PMID: 27025348 PMCID: PMC4820934 DOI: 10.1038/ncomms11086] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Accepted: 02/15/2016] [Indexed: 11/29/2022] Open
Abstract
If quenched fast enough, a liquid is able to avoid crystallization and will remain in a metastable supercooled state down to the glass transition, with an important increase in viscosity upon further cooling. There are important differences in the way liquids relax as they approach the glass transition, rapid or slow variation in dynamic quantities under moderate temperature changes, and a simple means to quantify such variations is provided by the concept of fragility. Here, we report molecular dynamics simulations of a typical network-forming glass, Ge-Se, and find that the relaxation behaviour of the supercooled liquid is strongly correlated to the variation of rigidity with temperature and the spatial distribution of the corresponding topological constraints, which ultimately connect to the fragility minima. This permits extending the fragility concept to aspects of topology/rigidity, and to the degree of homogeneity of the atomic-scale interactions for a variety of structural glasses.
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Affiliation(s)
- C. Yildirim
- Laboratoire de Physique Théorique de la Matière Condensée, Paris Sorbonne Universités—UPMC, Boite 121, 4, Place Jussieu, 75252 Paris Cedex 05, France
- Physique des Solides, Interfaces et Nanostructures & CESAM, B5, Université de Liège, B4000 Sart-Tilman, Belgium
| | - J.-Y. Raty
- Physique des Solides, Interfaces et Nanostructures & CESAM, B5, Université de Liège, B4000 Sart-Tilman, Belgium
| | - M. Micoulaut
- Laboratoire de Physique Théorique de la Matière Condensée, Paris Sorbonne Universités—UPMC, Boite 121, 4, Place Jussieu, 75252 Paris Cedex 05, France
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11
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Pacaud F, Micoulaut M. Thermodynamic precursors, liquid-liquid transitions, dynamic and topological anomalies in densified liquid germania. J Chem Phys 2015; 143:064502. [DOI: 10.1063/1.4927707] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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12
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Hermansen C, Mauro JC, Yue Y. Response to "Comment on 'A model for phosphate glass topology considering the modifying ion sub-network"' [J. Chem. Phys. 142, 107103 (2015)]. J Chem Phys 2015; 142:107104. [PMID: 25770566 DOI: 10.1063/1.4913761] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
In our recent paper [C. Hermansen, J. C. Mauro, and Y.-Z. Yue, J. Chem. Phys. 140, 154501 (2014)], we applied temperature-dependent constraint theory to model the glass transition temperature (Tg) and liquid fragility index (m) of alkali phosphate glasses. Sidebottom commented on this paper concerning the m values obtained by differential scanning calorimetry (DSC) [D. L. Sidebottom, J. Chem. Phys. 142, ⬛ (2015)]. We have considered Sidebottom's comments carefully and conclude that the m values of phosphate liquids obtained by DSC are reliable, except for the NaPO3 and possibly P2O5 compositions. Based on his dynamic light scattering measurements, Sidebottom has found that P2O5 is a strong liquid with m ≈ 20. However, based on the heat capacity jump at Tg and the stretching exponent of the relaxation function, P2O5 should be classified as an intermediate fragile liquid with m ≈ 40. We also argue that m cannot be universally related to the average connectivity of the network and point out several inconsistencies with this view.
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Affiliation(s)
- Christian Hermansen
- Section of Chemistry, Aalborg University, Fredrik Bajers Vej 7H, 9220 Aalborg, Denmark
| | - John C Mauro
- Science and Technology Division, Corning Incorporated, Corning, New York 14831, USA
| | - Yuanzheng Yue
- Section of Chemistry, Aalborg University, Fredrik Bajers Vej 7H, 9220 Aalborg, Denmark
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Micoulaut M, Bauchy M, Flores-Ruiz H. Topological Constraints, Rigidity Transitions, and Anomalies in Molecular Networks. MOLECULAR DYNAMICS SIMULATIONS OF DISORDERED MATERIALS 2015. [DOI: 10.1007/978-3-319-15675-0_11] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Bauchy M, Kachmar A, Micoulaut M. Structural, dynamic, electronic, and vibrational properties of flexible, intermediate, and stressed rigid As-Se glasses and liquids from first principles molecular dynamics. J Chem Phys 2014; 141:194506. [DOI: 10.1063/1.4901515] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Affiliation(s)
- M. Bauchy
- Department of Civil and Environmental Engineering, University of California, Los Angeles, California 90095-1593, USA
| | - A. Kachmar
- Laboratoire de Physique Théorique de la Matière Condensée, Université Pierre et Marie Curie, 4 Place Jussieu, F-75252 Paris Cedex 05, France
- Qatar Environment and Energy Research Institute, Qatar Foundation, P.O. Box 5825, Doha, Qatar
| | - M. Micoulaut
- Laboratoire de Physique Théorique de la Matière Condensée, Université Pierre et Marie Curie, 4 Place Jussieu, F-75252 Paris Cedex 05, France
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Hermansen C, Mauro JC, Yue Y. A model for phosphate glass topology considering the modifying ion sub-network. J Chem Phys 2014. [DOI: 10.1063/1.4870764] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Ravindren S, Gunasekera K, Tucker Z, Diebold A, Boolchand P, Micoulaut M. Crucial effect of melt homogenization on the fragility of non-stoichiometric chalcogenides. J Chem Phys 2014; 140:134501. [DOI: 10.1063/1.4869107] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Chakraborty S, Boolchand P. Topological origin of fragility, network adaptation, and rigidity and stress transitions in especially homogenized nonstoichiometric binary Ge(x)S(100-x) glasses. J Phys Chem B 2014; 118:2249-63. [PMID: 24471439 DOI: 10.1021/jp411823j] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Binary GexS100-x glasses reveal a richness of elastic and chemical phase transitions driven by network topology. With increasing Ge content (x), well-defined rigidity at xc(1) = 19.3(5)% and a stress transition at xc(2) = 24.9(5)% are observed in Raman scattering. In modulated DSC measurements, the nonreversing enthalpy of relaxation at Tg reveals a square-well-like minimum (reversibility window) with window walls that coincide with the two elastic phase transitions. Molar volumes show a trapezoidal-like minimum (volumetric window) with edges that nearly coincide with the reversibility window. These optical, thermal, and volumetric results are consistent with an isostatically rigid elastic phase (intermediate phase, IP) present between the rigidity (xc(1)) and stress (xc(2)) transitions. Complex Cp measurements show melt fragility index, m(x) to also show a global minimum in the reversibility window with m < 20, underscoring that melt dynamics encode the elastic behavior of the glass formed at Tg. The strong nature of melts formed in the IP has an important practical consequence; they lead to slow homogenization (over days not hours) of nonstoichiometric Ge-S batch compositions reacted at high temperatures. Homogenization of chalcogenide melts/glasses over a scale of a few micrometers is a prerequisite to observe the intrinsic physical properties of these materials.
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Affiliation(s)
- Shibalik Chakraborty
- Department of Electronic and Computing Systems, College of Engineering and Applied Science, University of Cincinnati , Cincinnati, Ohio 45220-0030, United States
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