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Abstract Magneto‐optical (MO) coupling incorporates photon‐induced change of magnetic polarization that can be adopted in ultrafast switching, optical isolators, mode convertors, and optical data storage components for advanced optical integrated circuits. However, integrating plasmonic, magnetic, and dielectric properties in one single material system poses challenges since one natural material can hardly possess all these functionalities. Here, co‐deposition of a three‐phase heterostructure composed of a durable conductive nitride matrix with embedded core–shell vertically aligned nanopillars, is demonstrated. The unique coupling between ferromagnetic NiO core and atomically sharp plasmonic Au shell enables strong MO activity out‐of‐plane at room temperature. Further, a template growth process is applied, which significantly enhances the ordering of the nanopillar array. The ordered nanostructure offers two schemes of spin polarization which result in stronger antisymmetry of Kerr rotation. The presented complex hybrid metamaterial platform with strong magnetic and optical anisotropies is promising for tunable and modulated all‐optical‐based nanodevices.
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This content will become publicly available on March 19, 2026
Simultaneous Incorporation of Magnetic and Plasmonic Nanocrystals in a Chiral Conducting Polymer Yields Unprecedented Magneto‐Optic Response
Abstract The creation of next‐generation flexible and conformable magneto‐optic (MO) materials with dramatically enhanced Verdet constant will significantly advance technologies, including optical isolation, magnetic quantum spin fluctuation measurements, and cold atom spin coherence probes, while opening new possibilities for mapping weakly emanating magnetic fields from sources, including microelectronics or brain activity. The results presented here show that the natural coupling of electric and magnetic dipoles in a chiral polymer with large optical activity (circular birefringence) is significantly enhanced by combined plasmonic field and magnetic interactions of plasmonic nanostars and magnetic nanoparticles to yield a dramatically increased Verdet constant within an optical path of a few hundred nanometers. A 175 ± 10 nm film of this material produces up to 600 mdeg of relative MO rotation at 510 nm, which translates to a record‐high Verdet constant of 3.1 × 107deg T−1m−1at 93 K, more than two orders of magnitude higher than the current state of the art MO garnet crystals. The room temperature Verdet constant substantially exceeds that of other thin film nanocomposites reported to date. Manipulation of electric and magnetic coupling offers an unprecedented opportunity to tailor the magnitude, sign, and spectral dispersion of the Verdet constant over a broad range of wavelengths.
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- Award ID(s):
- 2242796
- PAR ID:
- 10580602
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Small
- ISSN:
- 1613-6810
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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