Colloidal polymers with tunable chain stiffness have been successfully assembled in experiments recently.Similar to molecular polymers,chain stiffness is an important feature which can distinctly affect the dynamical ...Colloidal polymers with tunable chain stiffness have been successfully assembled in experiments recently.Similar to molecular polymers,chain stiffness is an important feature which can distinctly affect the dynamical behaviors of colloidal polymers.Hence,we model colloidal polymers with controlled chain stiffness and study the effect of chain stiffness on glassy behaviors.For stiff chains,there are long-ranged periodic intrachain correlations besides two incompatible local length scales,i.e.,monomer size and bond length.The mean square displacement of monomers exhibits sub-diffusion at intermediate time/length scale and the sub-diffusive exponent increases with chain stiffness.The data of localization length of stiff polymers versus rescaled volume fraction for different monomer sizes can gather close to an exponential curve and decay slower than those of flexible polymers.The increase of chain stiffness linearly increases the activation energy of the colloidal-polymer system and thus makes the colloidal polymers vitrify at lower volume fraction.Static and dynamic equivalences between stiff colloidal polymers of different monomer sizes have been checked.展开更多
Glassy matter,as metastable materials with long-range structural disorder but short-range order,has attracted considerable research interest over the past decades due to their unique physical,chemical,and mechanical p...Glassy matter,as metastable materials with long-range structural disorder but short-range order,has attracted considerable research interest over the past decades due to their unique physical,chemical,and mechanical properties.However,the intrinsic structural heterogeneity and complex dynamic behaviors of these materials,especially in the supercooled liquid regime and the glassy state,remain central challenges in condensed matter physics and materials science[1,2].展开更多
On approaching the glass transition,the structural relaxation of glass-forming liquids slows down drastically,along with a significant growth of dynamic heterogeneity.Recent studies have achieved substantial advanceme...On approaching the glass transition,the structural relaxation of glass-forming liquids slows down drastically,along with a significant growth of dynamic heterogeneity.Recent studies have achieved substantial advancements in elucidating the quantitative correlations between structural relaxation and dynamic heterogeneity.Here,we present the discovery of a novel dynamic crossover with possibly universal dynamic signatures by investigating the relationship between structural relaxation and dynamic heterogeneity.Specifically,the structural relaxation time at the dynamic crossoverτ_(c)is equal to the time scale for the maximum non-Gaussian parameter,which could serve as a quantitative characterization of dynamic heterogeneity.The degree of dynamic heterogeneity at the crossover is approximately equivalent across all investigated glass-forming liquids,leading to a scaling collapse between structural relaxation and dynamic heterogeneity.Moreover,the mean squared displacement at the structural relaxation time is nearly constant across different temperatures as long as the structural relaxation time does not exceedτ_(c).We further observe that the temperature at the dynamic crossover is lower than the onset temperature of slow dynamics.Our findings thus suggest the existence of a novel dynamic crossover with possibly universal dynamic signatures in glass-forming liquids,which merits in-depth investigations.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11804085 and 11847115)the Doctoral Foundation of Heze University(Grant No.XY18BS13).
文摘Colloidal polymers with tunable chain stiffness have been successfully assembled in experiments recently.Similar to molecular polymers,chain stiffness is an important feature which can distinctly affect the dynamical behaviors of colloidal polymers.Hence,we model colloidal polymers with controlled chain stiffness and study the effect of chain stiffness on glassy behaviors.For stiff chains,there are long-ranged periodic intrachain correlations besides two incompatible local length scales,i.e.,monomer size and bond length.The mean square displacement of monomers exhibits sub-diffusion at intermediate time/length scale and the sub-diffusive exponent increases with chain stiffness.The data of localization length of stiff polymers versus rescaled volume fraction for different monomer sizes can gather close to an exponential curve and decay slower than those of flexible polymers.The increase of chain stiffness linearly increases the activation energy of the colloidal-polymer system and thus makes the colloidal polymers vitrify at lower volume fraction.Static and dynamic equivalences between stiff colloidal polymers of different monomer sizes have been checked.
文摘Glassy matter,as metastable materials with long-range structural disorder but short-range order,has attracted considerable research interest over the past decades due to their unique physical,chemical,and mechanical properties.However,the intrinsic structural heterogeneity and complex dynamic behaviors of these materials,especially in the supercooled liquid regime and the glassy state,remain central challenges in condensed matter physics and materials science[1,2].
基金support from the National Natural Science Foundation of China(Grant Nos.12374202 and 12004001)Anhui Projects(Grant Nos.2022AH020009,S020218016,and Z010118169),and Hefei City(Grant No.Z020132009)+3 种基金support from the National Natural Science Foundation of China(Grant Nos.T2325004 and 52161160330)Advanced Materials-National Science and Technology Major Project(Grant No.2024ZD0606900)the Talent Hub for“AI+New Materials”Basic ResearchHefei Advanced Computing Center,Beijing Super Cloud Computing Center,and the High-Performance Computing Platform of Anhui University for providing computing resources.
文摘On approaching the glass transition,the structural relaxation of glass-forming liquids slows down drastically,along with a significant growth of dynamic heterogeneity.Recent studies have achieved substantial advancements in elucidating the quantitative correlations between structural relaxation and dynamic heterogeneity.Here,we present the discovery of a novel dynamic crossover with possibly universal dynamic signatures by investigating the relationship between structural relaxation and dynamic heterogeneity.Specifically,the structural relaxation time at the dynamic crossoverτ_(c)is equal to the time scale for the maximum non-Gaussian parameter,which could serve as a quantitative characterization of dynamic heterogeneity.The degree of dynamic heterogeneity at the crossover is approximately equivalent across all investigated glass-forming liquids,leading to a scaling collapse between structural relaxation and dynamic heterogeneity.Moreover,the mean squared displacement at the structural relaxation time is nearly constant across different temperatures as long as the structural relaxation time does not exceedτ_(c).We further observe that the temperature at the dynamic crossover is lower than the onset temperature of slow dynamics.Our findings thus suggest the existence of a novel dynamic crossover with possibly universal dynamic signatures in glass-forming liquids,which merits in-depth investigations.
