Tunable opto-magnetic metamaterials via coupled TiN-NiO vertically aligned nanocomposite thin films

Area of Science:

• Materials Science
• Nanotechnology
• Optoelectronics

Background:

• Hybrid metamaterials integrate plasmonic and magnetic properties for tunable light-matter interactions.
• Vertically aligned nanocomposites (VANs) offer unique structural control for advanced material properties.

Purpose of the Study:

• To investigate the effect of laser pulse frequency on the microstructure and properties of titanium nitride-nickel oxide (TiN-NiO) VANs.
• To explore the tunability of optical anisotropy and magnetic response by controlling NiO pillar density.

Main Methods:

• Pulsed laser deposition (PLD) was used to grow TiN-NiO VAN thin films at varying laser frequencies (2, 5, 10 Hz).
• Structural, morphological, ellipsometry, and magnetic hysteresis measurements were employed for characterization.

Main Results:

• Increasing laser frequency enhanced NiO pillar density, allowing structural modulation.
• Higher frequencies led to increased optical anisotropy and Type-II hyperbolic dispersion.
• Ferromagnetic behavior was observed at 10 K and 300 K, with enhanced coercivity and out-of-plane anisotropy correlating with pillar morphology.

Conclusions:

• Laser pulse frequency is a critical parameter for tuning the optical and magnetic properties of TiN-NiO VANs.
• Controlled microstructure enables enhanced light-matter interactions and magnetic responses.
• These findings pave the way for novel technologies in data storage, communication, and optoelectronics.