[institut] SCL seminar, Vladimir Dobrosavljevic, cetvrtak 7. maj u 13:00

[Darko Tanaskovic]

Поштоване колегинице и колеге,

Позивам вас на семинар Лабораторије за примену рачунара у науци који ће 
у четвртак 7. maja у 13:00 у читаоници "Др Драган Поповић" Института за 
физику одржати др Владимир Добросављевић (Department of Physics and 
NHMFL, Florida State University). Наслов семинара је:


Geometrically frustrated Coulomb systems


Abstract

We show [1] that introducing long-range Coulomb interactions 
immediately lifts the massive ground state degeneracy induced by 
geometric frustration for electrons on quarter-filled triangular 
lattices in the classical limit. Important consequences include the 
stabilization of a stripe-ordered crystalline (global) ground state, but 
also the emergence of very many low-lying metastable states with 
amorphous "stripe-glass" spatial structures [2]. Melting of the stripe 
order thus leads to a frustrated Coulomb liquid at intermediate 
temperatures, showing remarkably slow (viscous) dynamics, with very long 
relaxation times growing in Arrhenius fashion upon cooling, as typical 
of strong glass formers. On shorter time scales, the system falls out of 
equilibrium and displays the aging phenomena characteristic of 
super-cooled liquids around the glass transition. Our results show 
remarkable similarity with the recent observations [3,4] of charge-glass 
behavior in ultra-clean triangular organic materials of the θ-(BEDT-TTF) 
family.

1.S. Mahmoudian, L. Rademaker, A. Ralko, S. Fratini, V. Dobrosavljević, 
submitted to Phys. Rev. Lett., preprint arXiv:1412.4441.
2.J. Schmalian and P. G. Wolynes, Phys. Rev. Lett. 85, 836 (2000).
3.F. Kagawa, T. Sato, K. Miyagawa, K. Kanoda, Y. Tokura, K. Kobayashi, 
R. Kumai, and Y. Murakami, Nat. Phys. 9, 422 (2013).
4.H. Oike, F. Kagawa, N. Ogawa, A. Ueda, H. Mori, M. Kawasaki, and Y. 
Tokura, Phys. Rev. B 91, 041101 (2015).

Срдачан поздрав,
Дарко Танасковић