Resonant magneto-optical Kerr effect induced by hybrid plasma modes in ferromagnetic nanovoids

Resonant magneto-optical Kerr effect induced by hybrid plasma modes in ferromagnetic nanovoids

Xia Zhang;Lei Shi;Jing Li;Yun-Jie Xia;Shi-Ming Zhou

【期刊名称】《中国物理：英文版》 【年(卷),期】2017(026)011

【摘要】With nanovoids buried in Co films,resonant structures were observed in spectra of polar magneto-optical Kerr effect (MOKE),where both a narrow bandwidth and high intensity were acquired.Through changing the thickness of Co films and the lattice of voids,different optical modes were introduced.For a very shallow array of voids,the resonant MOKE was induced by Ag plasma edge resonance,for deeper ones,hybrid plasma modes,such as void plasmons in the voids,surface lattice

plasmons

between

the

voids,and

the

co-action

of

them,etc.resulted in resonant MOKE.We found that resonant MOKE resulted from the void plasmons resonance which possesses the narrowest bandwidth for the lowest absorption of voids.The simulated electromagnetic field (EF) distribution consolidated different effects of these three optical modes on resonant MOKE modulation.Such resonant polar MOKE possesses high sensitivity,which might pave the way to on-chip MO devices. 【总页数】9页(489-497) 【关键词】