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arXiv · 1406.4981

Band structure of magnonic crystals with defects: Brillouin spectroscopy and micromagnetic simulations

Kai Di·Vanessa Li Zhang·Meng Hau Kuok·Hock Siah Lim·Ser Choon Ng·Kulothungasagaran Narayanapillai·Hyunsoo Yang
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Abstract

Using Brillouin spectroscopy, the first observation has been made of the band structures of nanostructured defect magnonic crystals. The samples are otherwise one-dimensional periodic arrays of equal-width Ni80Fe20 and cobalt nanostripes, where the defects are stripes of a different width. A dispersionless defect branch emerges within the bandgap with a frequency tunable by varying the defect stripe width, while the other branches observed are similar to those of a defect-free crystal. Micromagnetic and finite-element simulations performed unveil additional tiny bandgaps and the frequency-dependent localization of the defect mode in the vicinity of the defects.

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Kai Di, Vanessa Li Zhang, Meng Hau Kuok, Hock Siah Lim, Ser Choon Ng, Kulothungasagaran Narayanapillai, Hyunsoo Yang. 2014-06-19. Band structure of magnonic crystals with defects: Brillouin spectroscopy and micromagnetic simulations. https://doi.org/10.1103/physrevb.90.060405

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