Machine-Learning-Assisted Materials Discovery from Electronic Band Structure.

Traditional methods of materials discovery, often relying on intuition and trial-and-error experimentation, are time-consuming and limited in their ability to explore the vast design space effectively. The emergence of machine learning (ML) as a powerful tool for pattern recognition has opened exciting opportunities to revolutionize materials discovery. This work explores the application of ML techniques to assist in the discovery of materials using band structure data.

Tunable insulator-metal transition in epitaxial VO thin films strain and defect engineering.

The Metal to Insulator Transition (MIT) in materials, particularly vanadium dioxide (VO), has garnered significant research interest due to its potential applications in smart windows, memristors, transistors, sensors, and optical switches. The transition from an insulating, monoclinic phase to a conducting, tetragonal phase involves changes in optical and electrical properties, opening avenues in adaptive radiative coolers, optical memories, photodetectors, and optical switches. VO exhibits MIT close to 68 °C, thereby requiring tuneable transition temperatures ( ) in VO thin films for practical device applications.

Review on the growth, properties and applications of self-assembled oxide-metal vertically aligned nanocomposite thin films-current and future perspectives.

Self-assembled oxide-metal nanocomposite thin films have aroused great research interest owing to their wide range of functionalities, including metamaterials with plasmonic and hyperbolic optical properties, and ferromagnetic, ferroelectric and multiferroic behaviors. Oxide-metal nanocomposites typically self-assemble as metal particles in an oxide matrix or as a vertically aligned nanocomposite (VAN) with metal nanopillars embedded in an oxide matrix. Among them, the VAN architecture is particularly interesting due to the vertical strain control and highly anisotropic structure, enabling the epitaxial growth of materials with large lattice mismatch.

Self-Assembled BaTiO-AuAg Low-Loss Hybrid Plasmonic Metamaterials with an Ordered "Nano-Domino-like" Microstructure.

Metallic plasmonic hybrid nanostructures have attracted enormous research interest due to the combined physical properties coming from different material components and the broad range of applications in nanophotonic and electronic devices. However, the high loss and narrow range of property tunability of the metallic hybrid materials have limited their practical applications. Here, a metallic alloy-based self-assembled plasmonic hybrid nanostructure, i.

Thermal stability of self-assembled ordered three-phase Au-BaTiO-ZnO nanocomposite thin films heating in TEM.

Thermal stability of oxide-metal nanocomposites is important for designing practical devices for high temperature applications. Here, we study the thermal stability of the self-assembled ordered three-phase Au-BaTiO3-ZnO nanocomposite by both ex situ annealing under air and vacuum conditions, and by in situ heating in TEM in a vacuum. The study reveals that the variation of the annealing conditions greatly affects the resulting microstructure and the associated dominant diffusion mechanism.

Au-Encapsulated Fe Nanorods in Oxide Matrix with Tunable Magneto-Optic Coupling Properties.

Materials with magneto-optic coupling properties are highly coveted for their potential applications ranging from spintronics and optical switches to sensors. In this work, a new, three-phase Au-Fe-LaSrFeO (LSFO) hybrid material grown in a vertically aligned nanocomposite (VAN) form has been demonstrated. This three-phase hybrid material combines the strong ferromagnetic properties of Fe and the strong plasmonic properties of Au and the dielectric nature of the LSFO matrix.

Bidirectional tuning of phase transition properties in Pt : VO nanocomposite thin films.

A phase transition material, VO, with a semiconductor-to-metal transition (SMT) near 341 K (68 °C) has attracted significant research interest because of drastic changes in its electrical resistivity and optical dielectric properties. To address its application needs at specific temperatures, tunable SMT temperatures are highly desired. In this work, effective transition temperature (T) tuning of VO has been demonstrated via a novel Pt : VO nanocomposite design, i.

Tunable physical properties in BiAl Mn O thin films with novel layered supercell structures.

Morphological control in oxide nanocomposites presents enormous opportunities for tailoring the physical properties. Here, we demonstrate the strong tunability of the magnetic and optical properties of Bi-based layered supercell (LSC) multiferroic structures, , BiAl Mn O by varying the Al : Mn molar ratio. The microstructure of the LSC structure evolves from a supercell structure to Al-rich pillars in the supercell structure as the Al molar ratio increases.

Breaking Lattice Symmetry in Highly Strained Epitaxial VO Films on Faceted Nanosurface.

The lattice symmetry of strongly correlated oxide heterostructures determines their exotic physical properties by coupling the degrees of freedom between lattices and electrons, orbitals, and spin states. Systematic studies on VO, a Mott insulator, have previously revealed that lattice distortion can be manipulated by the interfacial strain and electronic phase separation can emerge. However, typical epitaxial film-substrate interface strain provides a very limited range for exploring such interface-engineered phenomena.

Tuning magnetic anisotropy in Co-BaZrO vertically aligned nanocomposites for memory device integration.

Ferromagnetic nanostructures with strong anisotropic properties are highly desired for their potential integration into spintronic devices. Several anisotropic candidates, such as CoFeB and Fe-Pt, have been previously proposed, but many of them have limitations such as patterning issues or thickness restrictions. In this work, Co-BaZrO (Co-BZO) vertically aligned nanocomposite (VAN) films with tunable magnetic anisotropy and coercive field strength have been demonstrated to address this need.

Self-Assembled Ordered Three-Phase Au-BaTiO -ZnO Vertically Aligned Nanocomposites Achieved by a Templating Method.

Complex multiphase nanocomposite designs present enormous opportunities for developing next-generation integrated photonic and electronic devices. Here, a unique three-phase nanostructure combining a ferroelectric BaTiO , a wide-bandgap semiconductor of ZnO, and a plasmonic metal of Au toward multifunctionalities is demonstrated. By a novel two-step templated growth, a highly ordered Au-BaTiO -ZnO nanocomposite in a unique "nanoman"-like form, i.

Tailorable Au Nanoparticles Embedded in Epitaxial TiO Thin Films for Tunable Optical Properties.

The unique property of plasmonic materials to localize light into deep sub-wavelength regime has greatly driven various applications in the field of photovoltaics, sensors, and photocatalysis. Here, we demonstrate the one-step growth of an oxide-metal hybrid thin film incorporating well-dispersed gold (Au) nanoparticles (NPs) with tailorable particle shape and diameters (ranging from 2 to 20 nm) embedded in highly epitaxial TiO matrix, deposited using pulsed laser deposition. Incorporation of Au NPs reduces the band gap of TiO and enhances light absorption in the visible regime owing to the excitation of localized surface plasmons.

Microstructure, Magnetic, and Magnetoresistance Properties of LaSrMnO:CuO Nanocomposite Thin Films.

(LaSrMnO):(CuO) (LSMO:CuO) nanocomposite thin films were deposited on SrTiO (001), LaAlO (001), and MgO (001) substrates by pulsed laser deposition, and their microstructure as well as magnetic and magnetoresistance properties were investigated. X-ray diffraction (XRD) and transmission electron microscopy (TEM) results show that LSMO:CuO films grow as highly textured self-assembled vertically aligned nanocomposite (VAN), with a systematic domain structure and strain tuning effect based on the substrate type and laser deposition frequency. A record high low-field magnetoresistance (LFMR) value of ∼80% has been achieved in LSMO:CuO grown on LaAlO (001) substrate under high frequency.

Novel Layered Supercell Structure from BiAlMnO for Multifunctionalities.

Layered materials, e.g., graphene and transition metal (di)chalcogenides, holding great promises in nanoscale device applications have been extensively studied in fundamental chemistry, solid state physics and materials research areas.

Valley Polarization by Spin Injection in a Light-Emitting van der Waals Heterojunction.

The band structure of transition metal dichalcogenides (TMDCs) with valence band edges at different locations in the momentum space could be harnessed to build devices that operate relying on the valley degree of freedom. To realize such valleytronic devices, it is necessary to control and manipulate the charge density in these valleys, resulting in valley polarization. While this has been demonstrated using optical excitation, generation of valley polarization in electronic devices without optical excitation remains difficult.