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The integration of nanocomposite thin films with combined multifunctionalities on flexible substrates is desired for flexible device design and applications. For example, combined plasmonic and magnetic properties could lead to unique optical switchable magnetic devices and sensors. In this work, a multiphase TiN-Au-Ni nanocomposite system with core–shell-like Au-Ni nanopillars embedded in a TiN matrix has been demonstrated on flexible mica substrates. The three-phase nanocomposite film has been compared with its single metal nanocomposite counterparts, i.e., TiN-Au and TiN-Ni. Magnetic measurement results suggest that both TiN-Au-Ni/mica and TiN-Ni/mica present room-temperature ferromagnetic property. Tunable plasmonic property has been achieved by varying the metallic component of the nanocomposite films. The cyclic bending test was performed to verify the property reliability of the flexible nanocomposite thin films upon bending. This work opens a new path for integrating complex nitride-based nanocomposite designs on mica towards multifunctional flexible nanodevice applications. 

Abstract Hybrid metamaterials (HMs) have attracted significant research interests owing to their unique optical properties and their ability to manipulate light‐matter interaction in a novel and controlled fashion beyond what any single material offers. Especially 3D HMs are of great interest due to their potential to provide advanced and precise control of such light‐matter interaction in nanoscale. In this study, a set of 3D HM nanocomposite films are designed by integrating three phases, i.e., vertically aligned CoFe₂nanosheets within the matrix of TiN/TaN multilayers. By increasing the number of TiN/TaN multilayers from 2 to 19, a high degree of tunability in optical property has been demonstrated, including well‐tailored optical permittivity, and tunable hyperbolic dispersion from Type‐II to Type‐I. Ferromagnetic CoFe₂nanosheets introduces novel magnetic responses, such as magnetic anisotropy and enhanced coercivity. Furthermore, in situ heating X‐ray diffraction (XRD) suggests good thermal stability of the 3D nanocomposite films up to the measured temperature of 600 °C. This three‐phase 3D nanocomposite design offers more flexibility in HM designs, multifunctionalities, and phase stability, compared with the typical two‐phase HMs toward future metamaterials by design. 

Combinatorial growth is capable of creating a compositional gradient for thin film materials and thus has been adopted to explore composition variation mostly for metallic alloy thin films and some dopant concentrations for ceramic thin films. This study uses a combinatorial pulsed laser deposition method to successfully fabricate two‐phase oxide–oxide vertically aligned nanocomposite (VAN) thin films of La_0.7Sr_0.3MnO₃(LSMO)‐NiO with variable composition across the film area. The LSMO‐NiO compositional gradient across the film alters the two‐phase morphology of the VAN through varying nanopillar size and density. Additionally, the magnetic anisotropy and magnetoresistance properties of the nanocomposite thin films increase with increasing NiO composition. This demonstration of a combinatorial method for VAN growth can increase the efficiency of nanocomposite thin film research by allowing all possible compositions of thin film materials to be explored in a single deposition. 

Highly promising performance for future computing applications is achieved based on a new materials design. 

Abstract Oxide‐based memristors are considered promising candidates for next‐generation memory and neuromorphic computing applications owing to their intrinsic resistive switching properties, non‐volatile storage, excellent device plasticity, and compatibility with current complementary metal‐oxide‐semiconductor (CMOS) technology. For the physical implementation of neuromorphic microchips, memristors with high power efficiency, reasonable on/off ratios, excellent device reliability, and enhanced plasticity are essential. In this work, a novel memristor design based on SrTiO₃‐CeO₂(S‐C) vertically aligned nanocomposite (VAN) is proposed, utilizing the highly defective vertical interfaces as migration channels for oxygen vacancies (). More interestingly the interface density (σ_int) and strain can be effectively tuned by the deposition parameters. Comprehensive analyses, including microstructural analysis, electrical characterization, and finite element modeling, reveal that S‐C VAN memristors with high interface density (HID) exhibit superior power efficiency and reduced device‐to‐device (D2D) variation. Additionally, the S‐C HID memristor demonstrates endurance up to 10¹²cycles and retains its resistance states for up to 10⁵s at room temperature. The improved plasticity of the S‐C HID memristor enables better linear modulation of conductance with minimal fluctuation over long cycles and across different devices. Furthermore, artificial neural networks (ANNs) incorporating the S‐C HID memristor achieve high accuracy (>95%) on multiple datasets, underscoring its potential for neuromorphic computing applications.