Physics Seminar
Thermodynamic stability of quasicrystals: From fluid dynamics to soft condensed matter
Speaker: Ron Lifshitz (Tel Aviv University and University of Liverpool)
Date: Wednesday 1 June 2022
Time: 15:00
Venue: N/3.28
The observation of quasicrystals in soft condensed matter has provided insight into the ongoing quest to understand their formation and thermodynamic stability. I shall explain the stability of certain quasicrystals, using surprisingly simple classical field theories, by making an analogy to Faraday waves. This will provide a recipe for designing pair potentials that yield a variety of periodic and aperiodic crystals with prescribed symmetry, as confirmed by molecular dynamics simulations. I shall attempt to identify a trend that might be emerging in going from fluid dynamics to soft matter, which may (or may not) eventually lead to an understanding of the stability of quasicrystals in complex metallic alloys.
Biography: Prof. Ron Lifshitz is a theoretical physicist working on a range of topics in two separate fields: Quasicrystals and Nanomechanics. His work on quasicrystals in the last decade is mainly concerned with unlocking the secret to their thermodynamic stability -- especially in the context of soft condensed matter -- and using it to control their self-assembly via pair-potential design. In addition, he studies the fundamentals of aperiodic long-range order and its effect on physical properties, currently focusing on the puzzling nature of single-electron quantum wave functions in quasicrystals. In the field of nanomechanics Prof. Lifshitz's studies range from the mesoscopic physics of phonons in confined geometries and their interaction with electrons, the classical dynamics of coupled nonlinear nanomechanical resonators and oscillators, and the quantum-mechanical behavior of human-made nanoscale devices, with an emphasis on nonlinear quantum dynamics.