Validity of the Stokes-Einstein Relation in Soft Colloids up to the Glass Transition

Research output: Contribution to journalArticle

Abstract

We investigate the dynamics of kinetically frozen block copolymer micelles of different softness across a wide range of particle concentrations, from the fluid to the onset of glassy behavior, through a combination of rheology, dynamic light scattering, and pulsed field gradient NMR spectroscopy. We additionally perform Brownian dynamics simulations based on an ultrasoft coarse- grained potential, which are found to be in quantitative agreement with experiments, capturing even the very details of dynamic structure factors S(Q, t) on approaching the glass transition. We provide evidence that for these systems the Stokes-Einstein relation holds up to the glass transition; given that it is violated for dense suspensions of hard colloids, our findings suggest that its validity is an intriguing signature of ultrasoft interactions.

Details

Authors
  • Sudipta Gupta
  • Joerg Stellbrink
  • Emanuela Zaccarelli
  • Christos N. Likos
  • Manuel Camargo
  • Peter Holmqvist
  • Juergen Allgaier
  • Lutz Willner
  • Dieter Richter
Organisations
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Physical Chemistry
Original languageEnglish
Article number128302
JournalPhysical Review Letters
Volume115
Issue number12
Publication statusPublished - 2015
Publication categoryResearch
Peer-reviewedYes