2012/04/30 by Ryuichi Shindou, Ryo Matsumoto, Shuichi Murakami +1 · 3 citations
Physics and Astronomy · #cond-mat.mes-hall #cond-mat.other
paper · pdf · doi:10.1103/physrevb.87.174427
published as Phys. Rev. B 87, 174427 (2013) · 12 pages, 7 figures
arxiv created 2013/05/25 · arxiv updated 2013/05/28
Topological phases have been explored in various fields in physics such as spintronics, photonics, liquid helium, correlated electron system and cold-atomic system. This leads to the recent foundation of emerging materials such as topological band insulators, topological photonic crystals and topological superconductors/superfluid. In this paper, we propose a topological magnonic crystal which provides protected chiral edge modes for magnetostatic spin waves. Based on a linearized Landau-Lifshitz equation, we show that a magnonic crystal with the dipolar interaction acquires spin-wave volume-mode band with non-zero Chern integer. We argue that such magnonic systems are accompanied by the same integer numbers of chiral spin-wave edge modes within a band gap for the volume-mode bands. In these edge modes, the spin wave propagates in a unidirectional manner without being scattered backward, which implements novel fault-tolerant spintronic devices.