Soft excitations in glassy systems: Universal statistics quasi localization disordered phonons and structural indicators

by Eran Bouchbinder

at Condensed Matter Theory Seminar

Wed, 21 Mar 2018, 13:30
Physics building (#54) room 207

Abstract

The structure properties and dynamics of glassy systems continue to pose great theoretical challenges Of particular interest are i the effects of disorder on the nature and statistics of soft low frequency excitations that play an essential role in the thermodynamics transport properties and strongly irreversible responses of these systems at low temperatures ii the relations between the underlying disorder induced structures and the dynamics of these systems In this talk I will review our recent progress in addressing these basic problems I will first establish the existence of non phononic soft harmonic excitations in atomistic calculations based on finite size scaling analysis and extreme value statistics considerations These excitations feature a disordered core characterized by an atomistic localization length decorated with a dipolar power law decay in space quasi localization and follow a universal gapless 4 density of states These results resolve a decades long debate in relation to the existence and properties of non phononic soft excitations in glasses which we show to be associated with the generic existence of frustration induced internal stresses Then I will discuss the interaction of these quasi localized glassy excitations with disordered phonons and their far reaching implications for structure dynamics relations in the context of irreversible plastic rearrangements upon nonlinear driving References: E Lerner G D ring and E Bouchbinder Phys Rev Lett 117 035501 2016 E Lerner and E Bouchbinder Phys Rev E 96 020104 R 2017 E Lerner and E Bouchbinder arXiv:1711 11263 2017 E Bouchbinder and E Lerner arXiv:1801 05170 2018 J Zylberg E Lerner Y Bar Sinai and E Bouchbinder PNAS 114 7289 2017 E Lerner and E Bouchbinder arXiv:1802 01131 2018

Created on 08-03-2018 by Bar Lev, Yevgeny (ybarlev)
Updaded on 08-03-2018 by Bar Lev, Yevgeny (ybarlev)