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Artificial superlattices composed of perovskite oxides serves as an essential platform for engineering coherent phonon transport by redefining the lattice periodicity, which strongly influences the lattice-coupled phase transitions in charge and spin degrees of freedom. However, previous methods of manipulating phonons have been limited to controlling the periodicity of superlattice, rather than utilizing complex mutual interactions that are prominent in transition metal oxides. In this study on oxide superlattices composed of ferromagnetic metallic SrRuO and quantum paraelectric SrTiO, phonon modulation by controlling the geometry of superlattice in atomic-scale precision is realized, demonstrating the coherent phonon engineering using structural and magnetic phase transitions. By modulating the interface density, coherent-incoherent crossover of the phonon transport at room temperature is observed, which is coupled with a change in interfacial structural continuity. Upon cooling, the close relation between phonon transport and multiple phase transitions is identified. In particular, the enhancement of the polar state in SrTiO layer at ≈200 K leads to the weakening of phonon coherence and a further reduction of thermal conductivity in superlattices compared to the bulk limit. These findings provide a guide to developing future thermoelectric nanodevices by engineering the coherence of phonons via the design of complex oxide heterostructures.
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http://dx.doi.org/10.1002/advs.202407382 | DOI Listing |
Phys Rev Lett
August 2025
Duke University, Thomas Lord Department of Mechanical Engineering and Materials Science, Durham, North Carolina 27708, USA.
Chiral phonons, which are characterized by rotational atomic motion, offer a unique mechanism for transferring angular momentum from phonons to electron spins and other angular momentum carriers. In this Letter, we present a theoretical investigation into the emergence of chiral phonons in a chiral hybrid organic-inorganic perovskite (HOIP) and their critical roles in rigid-body rotation, magnetic moment generation, and spin transport under nonthermal equilibrium conditions. We demonstrate that phonon angular momentum can modify the spin chemical potential via a proposed microscopic Barnett effect, leading to a spatially varying spin chemical potential at the metal/HOIP interface, which subsequently induces spin currents in an adjacent Cu layer, with a magnitude consistent with experimental observations.
View Article and Find Full Text PDFPhys Chem Chem Phys
September 2025
State Key Laboratory of Materials for Integrated Circuits, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China.
Selenium, as an important semiconductor material, exhibits significant potential for understanding lattice dynamics and thermoelectric applications through its thermal transport properties. Conventional empirical potentials are often unable to accurately describe the phonon transport properties of selenium crystals, which limits in-depth understanding of their thermal conduction mechanisms. To address this issue, this study developed a high-precision machine learning potential (MLP), with training datasets generated molecular dynamics simulations.
View Article and Find Full Text PDFRSC Adv
September 2025
Laboratory of Spectroscopic Characterization and Optical Materials, Faculty of Sciences, University of Sfax B.P. 1171 3000 Sfax Tunisia
Lithium metavanadate (LiVO) is a material of growing interest due to its monoclinic 2/ structure, which supports efficient lithium-ion diffusion through one-dimensional channels. This study presents a detailed structural, electrical, and dielectric characterization of LiVO synthesized a solid-state reaction, employing X-ray diffraction (XRD), scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS), and impedance/dielectric spectroscopy across a temperature range of 473-673 K and frequency range of 10 Hz to 1 MHz. XRD and Rietveld refinement confirmed high crystallinity and single-phase purity with lattice parameters = 10.
View Article and Find Full Text PDFSmall
September 2025
Phonon Engineering Research Center of Jiangsu Province, Center for Quantum Transport and Thermal Energy Science, Institute of Physics Frontiers and Interdisciplinary Sciences, School of Physics and Technology, Nanjing Normal University, Nanjing, 210023, China.
As a 2D material with distinctive ferroelectric properties, InSe offers significant potential for the applications in information memory and advanced data storage technologies. It also exhibits a complex phase diagram that is highly sensitive to temperature and pressure variations, resulting in diverse lattice configurations. While extensive studies have focused on the phase transition behavior of InSe, its impact on phonon transport remains largely unexplored.
View Article and Find Full Text PDFACS Appl Mater Interfaces
September 2025
Plasmonics and Perovskites Laboratory, Department of Materials Science and Engineering, IIT Kanpur, Kanpur, U.P. 208016, India.
Contrary to the state-of-the-art thermoelectrics, such as tellurides and selenides, the thermoelectric performance of earth-abundant and less toxic BiS has been found to be inferior primarily because of poor electron transport. Herein, a less explored approach of composite formation using nanoinclusions of two-dimensional (2D) MXene, a graphene-analogous material, in BiS has been adopted to tailor the transport properties in order to obtain enhanced thermoelectric figure of merit (). Highly conductive stacked sheets of TiCT MXene, incorporated into the matrix of BiS, facilitate smoother electron transport, resulting in significantly enhanced electrical conductivity.
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