BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Memento EPFL//
BEGIN:VEVENT
SUMMARY:IMX/IPHYS Talks - Towards Robust Structural Superlubricity
DTSTART:20250502T140000
DTEND:20250502T150000
DTSTAMP:20260921T175006Z
UID:bbc66159cc5071bff8f0683c8026aa03eb56d27ab990c2b26ed47919
CATEGORIES:Conferences - Seminars
DESCRIPTION:Dr. Yiming Song\, University of Basel\nTribology\, the study o
 f friction\, wear and lubrication\, plays a pivotal role in various techno
 logical applications and scientific disciplines. One of the most fascinati
 ng phenomena in modern tribology is structural superlubricity\, a near-zer
 o friction state enabled by incommensurate interfaces\, allowing virtually
  frictionless sliding. However\, its practical application is hindered by 
 several factors such as interfacial misorientation\, lattice defects\, and
  contact-induced deformation\, which are still not fully understood.\nIn t
 his talk\, I will present recent multiscale experimental efforts aiming to
  address these challenges. We have developed assembly and manipulation tec
 hniques for atomically flat\, single-crystalline heterogeneous layered mat
 erial pairs(e.g.\, graphite-hBN)\, which suppress the commensurate rotatio
 n observed in homogeneous interfaces\, thereby enabling robust microscale 
 superlubricity. Scaling up structural superlubricity towards macroscopic d
 imensions inevitably involves forming junctions between polycrystalline su
 rfaces. At corrugated graphene grain boundaries\, we observed unusual atom
 ic frictional behavior\, including negative friction coefficients and non-
 monotonic velocity dependence. Using advanced atomic force microscopy\, we
  identified the dominant energy dissipation mechanism as dynamic (un)buckl
 ing of dislocation protrusions at grain boundaries. Additionally\, we disc
 overed a novel frictional dissipation mechanism associated with moiré pat
 terns in grain regions\, where the moiré ridges deform under the single-a
 sperity contact\, storing elastic energy that is abruptly released upon in
 stability\, leading to an increase in energy dissipation. To overcome thes
 e limitations\, we proposed a “strong adhesion–crystallographic alignm
 ent” strategy to construct layered material/single-crystal metal systems
 . This approach eliminates grain boundaries and suppresses moiré undulati
 ons\, paving the way for scalable\, dry superlubric contacts. Our findings
  provide critical insights into the physical limitations of superlubricity
  in large-scale vdW contacts and offer new design principles for controlli
 ng friction.\n\nBio: Dr. Yiming Song is currently a Postdoctoral Researche
 r in the Department of Physics at the University of Basel. He previously h
 eld postdoctoral positions at both the University of Basel and University 
 of Giessen (Germany) and has since returned to Basel to continue his resea
 rch on tribology\, surface science\, and two-dimensional materials. He rec
 eived his Ph.D. in Mechanical Engineering from Tsinghua University\, where
  his research focused on micro- and nanotribology as well as the developme
 nt of in-situ characterization and testing instruments. His research inter
 ests lie at the intersection of tribology\, nanomechanics\, two-dimensiona
 l materials\, and surface science\, with a particular emphasis on structur
 al superlubricity and fundamental mechanisms of energy dissipation in slid
 ing contacts. Dr. Yiming Song has published 17 papers in prestigious inter
 national journals\, including Nature Materials\, Physical Review Letters\,
  Nature Communications\, PNAS\, Nano Letters\, ACS Nano and has authored o
 ne book chapter. His outstanding achievements have been recognized with th
 e “Spark” grant from the Swiss National Science Foundation (SNSF).\n\n
 \n 
LOCATION:BM 5202 https://plan.epfl.ch/?room==BM%205202 https://epfl.zoom.u
 s/j/64613657716
STATUS:CONFIRMED
END:VEVENT
END:VCALENDAR