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In phase-change memory devices, a material is cycled between glassy and crystalline states. The highly temperature-dependent kinetics of its crystallization process enables application in memory technology, but the transition has not been resolved on an atomic scale. Using femtosecond x-ray diffraction and ab initio computer simulations, we determined the time-dependent pair-correlation function of phase-change materials throughout the melt-quenching and crystallization process. We found a liquid-liquid phase transition in the phase-change materials AgInSbTe and GeSb at 660 and 610 kelvin, respectively. The transition is predominantly caused by the onset of Peierls distortions, the amplitude of which correlates with an increase of the apparent activation energy of diffusivity. This reveals a relationship between atomic structure and kinetics, enabling a systematic optimization of the memory-switching kinetics.
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http://dx.doi.org/10.1126/science.aaw1773 | DOI Listing |
Microsyst Nanoeng
September 2025
Center for Terahertz Waves, College of Precision Instrument and Optoelectronics Engineering, and the Key Laboratory of Optoelectronics Information and Technology (Ministry of Education), Tianjin University, Tianjin, 300072, China.
Terahertz communication systems demand versatile devices capable of simultaneously controlling propagating waves and surface plasmon polaritons (SPPs) in far-field (FF) and near-field (NF) channels, yet existing solutions are constrained by volatile operation, single-function limitations, and the inability to integrate NF and FF functionalities. Here, we present a nonvolatile reconfigurable terahertz metasurface platform leveraging the phase-change material GeSbTe(GST) to achieve on-demand dual-channel modulation-a first in the terahertz regime. By exploiting the stark conductivity contrast of GST between amorphous and crystalline states, our design enables energy-efficient switching between NF-SPP manipulation and FF-wavefront engineering without requiring continuous power input.
View Article and Find Full Text PDFInt J Biol Macromol
September 2025
Key Laboratory of Bio-Based Material Science and Technology of Ministry of Education, Northeast Forestry University, Harbin, 150040, China. Electronic address:
With the exhaustion of fossil fuels, prior phase change materials are characterized by such drawbacks as poor thermal conductivity, weak shape stability, and high costs. Therefore, the preparation of phase change materials with brilliant thermal-insulating properties, high thermal conductivity, and leakage-free properties has emerged as a crucial research focus. Herein, a sericultural mulberry branch-derived (SMB) composite phase change material was prepared by deep eutectic solvent pretreated SMB and vacuum-assisted impregnated paraffin wax with cupric oxide (CuO).
View Article and Find Full Text PDFSmall
September 2025
Institute of High Pressure Physics, School of Physical Science and Technology, Ningbo University, Ningbo, 315211, China.
Fundamentally understanding lattice dynamics and thermal transport behavior in liquid-like, partially occupied compounds remains a long-standing challenge in condensed matter physics. Here, the microscopic mechanisms are investigated underlying the ultralow thermal conductivity in ordered/liquid-like CuBiS by combining experimental methods with first-principles calculations. The ordered structure and liquid-like are first experimentally synthesized and characterized, partially Cu-atom occupied CuBiS structure with increasing temperature.
View Article and Find Full Text PDFACS Sustain Resour Manag
August 2025
Aragón Institute for Engineering Research (I3A), Thermal Engineering and Energy Systems Group, University of Zaragoza, Agustín de Betancourt Building, C/María de Luna 3, Zaragoza 50018, Spain.
Global and local sensitivity analyses are essential for identifying key parameters in life cycle assessment models. However, due to limited information on parameter uncertainty, they are often overlooked. This paper's objective is to address this gap by proposing a methodological framework for defining input sensitivity, for midpoint and end point indicators, and a quantitative approach for determining input uncertainties.
View Article and Find Full Text PDFJ Colloid Interface Sci
August 2025
School of Physics and Astronomy, Beijing Normal University, Beijing 100875, China. Electronic address:
Phase change materials (PCMs)-integrated solar-thermal-electric generators (STEGs) have emerged as a promising platform for sustainable solar energy harvesting, yet faces critical challenges including liquid phase instability, insufficient photothermal efficiency, and limited thermoelectric output. Herein, we engineered hierarchical photonic confinement through the assembly of plasmonic CuS nanoparticles, broadband-absorbing MoS nanosheets, and porous bacterial cellulose (BC). In this tripartite architecture, BC matrix provides robust structural integrity and enhances heat transfer via its 3D interconnected nanoporous structure; MoS nanosheets enable extended photon harvesting across the ultraviolet to near-infrared spectrum; CuS nanoparticles amplify near-field optical effects through localized surface plasmon resonance.
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