Realization of Rectangular Artificial Spin Ice and Direct Observation of High Energy Topology

Autor: Winder A. Moura-Melo, Sukarno Olavo Ferreira, Fabio S. Nascimento, Clotilde Costa, Gary Mathew Wysin, C. I. L. de Araujo, Paulo P. Freitas, Jérôme Borme, Afranio R. Pereira, Isabel Ribeiro
Jazyk: angličtina
Rok vydání: 2017
Předmět:
Zdroj: Scientific Reports, Vol 7, Iss 1, Pp 1-9 (2017)
Scientific Reports
Repositório Institucional da UFOP
Universidade Federal de Ouro Preto (UFOP)
instacron:UFOP
LOCUS Repositório Institucional da UFV
Universidade Federal de Viçosa (UFV)
instacron:UFV
ISSN: 2045-2322
DOI: 10.1038/s41598-017-14421-w
Popis: In this work, we have constructed and experimentally investigated frustrated arrays of dipoles forming two-dimensional artificial spin ices with different lattice parameters (rectangular arrays with horizontal and vertical lattice spacings denoted by a and b respectively). Arrays with three different aspect ratios γ = a/b = $$\sqrt{{\bf{2}}}$$ 2 , $$\sqrt{{\bf{3}}}$$ 3 and $$\sqrt{{\bf{4}}}$$ 4 are studied. Theoretical calculations of low-energy demagnetized configurations for these same parameters are also presented. Experimental data for demagnetized samples confirm most of the theoretical results. However, the highest energy topology (doubly-charged monopoles) does not emerge in our theoretical model, while they are seen in experiments for large enough γ. Our results also insinuate that the string tension connecting two magnetic monopoles in a pair vanishes in rectangular lattices with a critical ratio γ = γ c = $$\sqrt{{\bf{3}}}$$ 3 , supporting previous theoretical predictions.
Databáze: OpenAIRE
Externí odkaz:
Nepřihlášeným uživatelům se plný text nezobrazuje