caa a22 4500 445391200 CHVBK 20180317143047.0 cr unu---uuuuu 170323e20110801xx s 000 0 eng 10.1007/s10955-011-0272-1 doi (NATIONALLICENCE)springer-10.1007/s10955-011-0272-1 Hartmann Alexander Institut für Physik, Universität Oldenburg, 26111, Oldenburg, Germany aut Ground States of Two-Dimensional Ising Spin Glasses: Fast Algorithms, Recent Developments and a Ferromagnet-Spin Glass Mixture [Elektronische Daten] [Alexander Hartmann] Using advanced numerical approaches based on optimization algorithms, much progress has been achieved for the study of the ground-state and low-temperature behavior of two-dimensional Ising spin glasses. Recent results led to a rather good understanding of these systems in the framework of the droplet-scaling theory. In this work, a pedagogical description of such an optimization-based approach is given and a short review of corresponding recent results is presented. Furthermore, original results are presented for a special type of system which combines a ferromagnetic sub lattice with a spin-glass sub lattice. Results for exact ground-state calculations up to system size N=1448×1448 are given. Past results of similar systems gave evidence that such a system might exhibit a spin-glass phase at finite temperatures. Nevertheless, the present results do not support this notion. But, for a suitable balance between ferromagnetic and ±J spin-glass couplings, extremely large finite-size effects occur. Thus, when considering intermediate system sizes, the system looks as if it orders. Furthermore, although the system exhibits only a discrete set of interactions, a power-law behavior for the stiffness energy can be observed clearly for a large range of system sizes. This is in contrast to past studies of systems with discrete sets of bond values. Springer Science+Business Media, LLC, 2011 Spin glasses nationallicence Ground states nationallicence Optimization algorithms nationallicence Matching algorithms nationallicence Domain walls nationallicence Droplets nationallicence SLE processes nationallicence Journal of Statistical Physics Springer US; http://www.springer-ny.com 144/3(2011-08-01), 519-540 0022-4715 144:3<519 2011 144 10955 https://doi.org/10.1007/s10955-011-0272-1 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10955-011-0272-1 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Hartmann Alexander Institut für Physik, Universität Oldenburg, 26111, Oldenburg, Germany aut NATIONALLICENCE 773 0- Journal of Statistical Physics Springer US; http://www.springer-ny.com 144/3(2011-08-01), 519-540 0022-4715 144:3<519 2011 144 10955 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer