Pure Electric and Pure Magnetic Resonances in Near-Infrared Metal Double-Triangle Metamaterial Arrays

• 来源期刊: 中国物理快报（英文版）
• 年，卷（期）: 2011,（5）
• 页码范围: 218-221
• 页数: 4页
• 语种: 英文
• DOI: 10.1088/0256-307X/28/5/057302

摘要

We experimentally and numerically investigate the optical properties of metamaterial arrays composed of double partially-overlapped metallic nanotriangles fabricated by an angle-resolved nanosphere lithography.We demonstrate that each double-triangle can be viewed as an artificial magnetic element analogous to the conventional metal split-ring-resonator.It is shown that under normal-incidence conditions,individual double-triangle can exhibit a strong local magnetic resonance,but the collective response of the metamaterial arrays is purely electric because magnetic resonances of the two double-triangles in a unit cell having opposite openings are out of phase.For oblique incidences the metamaterial arrays are shown to support a pure magnetic response at the same frequency band.Therefore,switchable electric and magnetic resonances are achieved in double-triangle arrays.Moreover,both the electric and magnetic resonances axe shown to allow for a tunability over a large spectral range down to near-infrared.