Thursday 14 Nov 2013: Observing atomic dynamics during crystallisation from Ab initio molecular dynamics simulations
Dr Tae-Hoon Lee - Department of Chemistry, University of Cambridge
HAR/170 (3D Visualisation Suite) 14:00-15:00
Phase-change memories (PCMs) are one of the leading candidates for next-generation non-volatile memory devices. They use the intriguing properties of phase-change (PC) materials, which enable high scalability, high read/write speeds, and long read/write endurance. Moreover, many new applications have emerged in the field of utilizing PCM technology, such as the application for neuromorphic devices with a potential usage for the brain-inspired computing. A thorough knowledge of crystallization dynamics in PCMs is the key to not only understand the fundamental working principles in these devices, but also be able to find possible new applications based on PCM technology. This talk will describe our efforts in understanding crystallization in PC materials from ab initio molecular dynamics (AIMD) simulations. The detailed information on the dynamics of atoms and vacancies, observed from AIMD simulations, provides a comprehensive picture on how PC materials can crystallize so fast (within an order of ns) while also showing high amorphous stability. The further implications of simulation results, as well as the recent achievement of sub-nanosecond crystallization speed in PCMs, will be also discussed.