Abstract：

Achieving a glass with high stability is challenging due to the slow relaxation dynamics below the glass transition temperature. Here, we introduce a novel nonequilibrium technique, termed temperature swap, to produce glasses more stable than the fast-quenched one. It involves periodically alternating the temperature of systems between Tlow and Thigh, with the same staying time tw. Through molecular dynamics simulations, we verify the effectiveness of this method in multiple glass systems with different interacting potentials and dimensions. Under sufficient temperature differences (Thigh- Tlow), the potential energy of the glass decreases when Tlow is lower than the onset temperature Ton, and this energy drop becomes more pronounced for Tlow below the glass transition temperature Tg. Moreover, the temperature swap method is most effective within a certain range of tw that coincides with the characteristic time scale determined by phonon speed. Microscopically, this non-equilibrium treatment reduces the potential energy of glasses by significantly accelerating the relaxation dynamics. We find that the energy of different normal modes redistributes during the rapid temperature change. Compared to isothermal systems, the energy concentrates on the low-frequency modes, which are highly related to structural relaxation behaviors.

个人简介：

谭鹏，男，1982年生，复旦大学物理学系教授，国家杰出青年基金获得者。本科毕业于山东大学，博士毕业于复旦大学，在香港中文大学从事博士后研究，2014年入职复旦大学物理学系，2023年微纳电子器件与量子计算机研究院双聘。长期工作于软凝聚态物理和统计物理与复杂系统交叉领域，开展结晶和玻璃相变相关的研究。