2020/05/28 by Ilya Razdolski, Razdolski, Ilya, G. Armelles +4
Engineering · Materials Science · #FOS: Physical sciences #Gold and Silver Nanoparticles Synthesis and Applications #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Optics (physics.optics) #Other Condensed Matter (cond-mat.other) #Photonic and Optical Devices #Plasmonic and Surface Plasmon Research
paper · pdf · doi:10.48550/arxiv.2005.13889
openalex publication_date 2020/05/28 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Metallic nanostructures exhibit strong nonlinear-optical response at surface plasmon resonances, where the light-matter coupling efficiency is enhanced. An active modulation of this response can be realized by means of an external magnetic field. Here we utilize a nonlinear magneto-refractive effect in spintronic multilayer antennas to achieve a resonant 20% modulation in second harmonic generation (SHG) in the mid-infrared. We discuss mechanisms of this modulation and show that it cannot be explained by an unequal enhancement of the electromagnetic field in the two spin states of the multilayer. Instead, we propose a novel contribution to the nonlinear susceptibility, which relies on the spin-dependent electron mean free path in metals. In contrast to magneto-optics in ferromagnets, our approach results in no shift of the resonance and thus ensures that the largest SHG and its strongest modulation are simultaneously observed.