The investigation of physical processes across various temporal scales is essential for comprehending and forecasting the behavior of intricate systems over extended periods.Relaxation processes,which span 16 orders o...The investigation of physical processes across various temporal scales is essential for comprehending and forecasting the behavior of intricate systems over extended periods.Relaxation processes,which span 16 orders of magnitude,are a prime example of multiscale physical processes.However,the description of the relaxation process across multiple time spans is not yet clear.This study employs advanced flash differential scanning calorimetry to probe multiscale relaxation dynamics across various glass systems.We discovered that the relaxation behavior exhibits self-similar scaling across multiple time scales,arising from the accumulation of temporally fractal activation events.Due to the heterogeneous distribution of energy in the system,not every activation event contributes to global energy reduction.Microscopic mechanisms underlying the temporal fractal of activation events are proposed based on both experimental and simulation results.The temporal fractal serves as a critical link connecting microscopic activation events with macroscopic relaxation processes in disordered materials.This fractal framework provides a powerful approach for probing multiscale dynamics in complex systems.展开更多
Heat transport is a key energetic process in materials and devices. The reduced sample size, low dimension of the problem and the rich spectrum of material imperfections introduce fruitful phenomena at nanoscale. In t...Heat transport is a key energetic process in materials and devices. The reduced sample size, low dimension of the problem and the rich spectrum of material imperfections introduce fruitful phenomena at nanoscale. In this review, we summarize recent progresses in the understanding of heat transport process in low-dimensional materials, with focus on the roles of defects, disorder, interfaces, and the quantum- mechanical effect. New physics uncovered from computational simulations, experimental studies, and predictable models will be reviewed, followed by a perspective on open challenges.展开更多
基金supported by the Key R&D Program of Shandong Province(Grant Nos.2024CXGC010315,and 2022CXGC020308)the Taishan Scholars Program of Shandong Province(Grant No.tsqn201909010)+1 种基金the Key Basic and Applied Research Program of Guangdong Province(Grant No.2019B030302010)the National Natural Science Foundation of China(Grant Nos.51901139,51971120,and U1902221)。
文摘The investigation of physical processes across various temporal scales is essential for comprehending and forecasting the behavior of intricate systems over extended periods.Relaxation processes,which span 16 orders of magnitude,are a prime example of multiscale physical processes.However,the description of the relaxation process across multiple time spans is not yet clear.This study employs advanced flash differential scanning calorimetry to probe multiscale relaxation dynamics across various glass systems.We discovered that the relaxation behavior exhibits self-similar scaling across multiple time scales,arising from the accumulation of temporally fractal activation events.Due to the heterogeneous distribution of energy in the system,not every activation event contributes to global energy reduction.Microscopic mechanisms underlying the temporal fractal of activation events are proposed based on both experimental and simulation results.The temporal fractal serves as a critical link connecting microscopic activation events with macroscopic relaxation processes in disordered materials.This fractal framework provides a powerful approach for probing multiscale dynamics in complex systems.
基金supported by the National Natural Science Foundation of China(11222217)the State Key Laboratory of Mechanics and Control of Mechanical Structures,Nanjing University of Aeronautics and Astronautics(MCMS-0414G01)
文摘Heat transport is a key energetic process in materials and devices. The reduced sample size, low dimension of the problem and the rich spectrum of material imperfections introduce fruitful phenomena at nanoscale. In this review, we summarize recent progresses in the understanding of heat transport process in low-dimensional materials, with focus on the roles of defects, disorder, interfaces, and the quantum- mechanical effect. New physics uncovered from computational simulations, experimental studies, and predictable models will be reviewed, followed by a perspective on open challenges.
