Ferroelectric thin films grown on tensile substrates: Renormalization of the Curie-Weiss law and apparent absence of ferroelectricity

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Interfaces between magnetic and non‐magnetic materials play a crucial role in various magnetic heterostructures. The emergence of 2D van der Waals (vdW) magnets has introduced new opportunities for exploring proximity effects in vdW heterostructures. While the influence of magnetic layers on nearby non‐magnetic materials has been widely studied, it remains unclear whether non‐magnetic substrates can similarly modulate the intrinsic magnetic properties of 2D magnets, particularly their magnetic anisotropy. I

A semi-empirical universal model describing the temperature dependence of heat capacity is developed using the Laplace distribution as a physical basis and its log-logistic analogue as an analytical form. The proposed formulation unifies the classical Debye, Einstein, and Tarasov approaches and provides an accurate representation of experimental data for solids, liquids, and gases over the entire temperature range of their stability. The model has only two parameters: the characteristic temperature and the

We present an in-situ Lorentz Transmission Electron Microscopy (LTEM) investigation into the cumulative effects of pulsed laser excitation on the metamagnetic transition in freestanding FeRh thin films. Our experiments demonstrate that repeated ultrafast laser pulses progressively introduce defects and associated residual strains, which promote the ferromagnetic phase and change the nucleation process from a homogeneous to a heterogeneous mechanism. This evolution is marked by a significant 20 K reduction i

Motivated by the recent observation of a uniform vector chirality (UVC) magnetic order in the maple-leaf lattice (MLL) realization

\mathrm{Ho_3ScO_6}

via powder neutron scattering experiments, we investigate the classical antiferromagnetic Heisenberg model on the maple-leaf lattice. The MLL features three symmetry-inequivalent nearest-neighbor couplings,

J_d

J_t

, and

J_h

. Previous studies, primarily focused on the case where

J_t = J_h

, identified a staggered vector chirality (SVC) order. Extendin

Spin caloritronics refers to research efforts in spintronics when a heat current plays a role. In this review, we start out by reviewing the predictions that can be drawn from the thermodynamics of irreversible processes. This serves as a conceptual framework in which to analyze the interplay of charge, spin and heat transport. This formalism predicts tensorial relations between vectorial quantities such as currents and gradients of chemical potentials or of temperature. Transverse effects such as the Nerns

High-temperature superconductivity emerges on doping holes or electrons into antiferromagnetic copper oxides. The large energy scale of magnetic excitations, for example, compared with phonon energies, is thought to drive superconductivity with high transition temperatures (T c). Comparing high-energy magnetic excitations of hole- and electron-doped superconductors provides an opportunity to test this hypothesis. Here, we use resonant inelastic X-ray scattering at the Cu L 3 -edge to reveal collective excit

It was noticed long time ago that the dielectric permittivity of BaTiO3 single crystals in the rhombohedral phase varies from observation to observation, but the microstructure mechanism behind this phenomenon remained unclear. We show that the variations in susceptibility can be related to the variable domain structure introduced by different pre-treatments at higher temperatures: Electrical depoling at room temperature leads to nano-sized domains and ultrahigh susceptibility in rhombohedral phase, whereas

We present magnetization and Se-77 Nuclear Magnetic Resonance (NMR) measurements in single crystals of the magnetoelectric compound Cu2OSeO3. The temperature and field dependence of the magnetization suggest a ferrimagnetic ordering at T-c similar or equal to 60 K in a 3up-1down configuration. The easy axis of the magnetization is along the [100] crystallographic direction. The Se-77 NMR line shape data collected at 14.09 T are consistent with the symmetries imposed by the cubic P2(1)3 space group in the te

A fundamental understanding of the quench phenomenon is particularly important in the design and operation of magnets using High Temperature Superconductors because the quench propagation velocity is low due to high specific heat at high temperature. We have performed the simulations of a high-current forced-flow conductor model to assess the key quench parameters, e. g. the temperature increase of the normal zone and its propagation velocity, using the CryoSoft code THEA. The sensitivity of these results o

This paper focuses on the fabrication and evaluation of vibration energy harvesting devices by utilizing an epitaxial Pb(Zr0.2Ti0.8)O-3 (PZT) thin film. The high quality of the c-axis oriented PZT layer results in a high piezoelectric coefficient and a low dielectric constant, which are key parameters for realizing high performance piezoelectric energy harvesters. Different cantilever structures, with and without a Si proof mass, are realized using micro-patterning techniques optimized for the epitaxial oxi

We report on the temperature dependence of ferroelectric metal-oxide-semiconductor (MOS) transistors and explain the observed improved characteristics based on the dielectric response of ferroelectric materials close to the Curie temperature. The hysteretic current-voltage static characteristics of a fully depleted silicon-on-insulator transistor, with 40 nm vinylidene fluoride trifluorethylene, and 10 nm SiO2 gate stack, are measured from 300 to 400 K. In contrast with conventional MOS field effect transis

Pb(Zr, Ti)O-3 (PZT) is an interesting material for bulk acoustic wave resonator applications due to its high electromechanical coupling constant, which would enable fabrication of large bandwidth frequency filters. The major challenge of the PZT solid solution system is to overcome mechanical losses generally observed in PZT ceramics. To increase the understanding of these losses in textured thin films, thin film bulk acoustic resonators (TFBAR's) based on PZT thin films with compositions either in the tetr

We discuss the structural, electronic and dielectric properties of a model structure of the Si(100)-SiO2 interface that accounts for the amorphous nature of the oxide. After showing that the structural properties of this model are consistent with a variety of experimental data, we consider the variation of the valence and conduction band edges across the interface. Our calculations indicate that the width of the electronic structure transition from the substrate to the oxide is 0.7-0.8 nm. We also address t

In ferroelectric materials, domain wall displacement plays a key role in the dielectric properties measured with respect to the driving field amplitude and frequency. The low to medium field dielectric response in many ferroic systems can be often described by classical Rayleigh model, which is rate-independent i.e., it depends only on the strength of ac signal. However experiments show that the nonlinear parameters are frequency dependent. Thus a more general approach, which can describe both purely nonlin

The results of structural and electrical characterizations of SrTiO3 thin films deposited onto MgO and LaAlO3 substrates by pulsed laser deposition technique are presented. The influence of substrate and annealing procedure on the crystalline structure and dielectric properties of these ferroelectric thin films are investigated. The obtained experimental data are analyzed in terms of the Landau theory taking into account the room-temperature lattice mismatch of the ferroelectric and substrates as well as th

The original magnetic properties of nanometre-sized particles are due to the distinct contributions of volume, surface and step atoms. To disentangle these contributions is an ongoing challenge of materials science. Here we introduce a method enabling the identification. of the remarkably different contributions of surface and perimeter atoms to the magnetic anisotropy energy of two-dimensional nanostructures. Our method uses the generally nonlinear relationship between perimeter length and surface area. At

The orientation dependence of the longitudinal piezoelectric coefficient, d(33)(), is investigated as a function of temperature in BaTiO3 and PbTiO3 crystals using the Landau-Ginsburg-Devonshire theory. We show that a presence of the ferroelectric-ferroelectric phase transitions in BaTiO3 leads to enhanced d(33)() along nonpolar directions. The reason for this is that in the vicinity of a phase transition temperature at which a polarization vector changes its direction (tetragonal-orthorhombic/monoclinic,

We report the transient optical pump-probe reflectivity measurements on single and double layer cuprate single crystals and thin films of ten different stoichiometries. We find that with sufficiently low fluence the relaxation time (tau(R)) of all samples exhibits a power law divergence with temperature (T): tau(R proportional to) T-3 +/-0.5. Further, the divergence has an onset temperature above the superconducting transition temperature for all superconducting samples. Possible causes of this divergence a

Properties of carrier-induced ferromagnetism in modulation-doped quantum wells of p-type (Cd,Mn)Te are assessed by photoluminescence (PL) and PL excitation spectroscopy. Well-chosen illumination makes it possible to deplete the quantum well and thus to control the strength of the ferromagnetic interactions. Spontaneous local magnetization is proportional to the hole concentration p but the Curie temperature T-C varies little over a wide p range, in agreement with the mean-field model for 2D systems. The spa

The printing of lead zirconate titanate (PZT, Pb(Zr,Ti)O-3) piezoelectric thick films on silicon substrates is being studied for potential use as microactuators, microsensors, and micro.. transducers. A fundamental challenge in the fabrication of useful PZT thick-film devices on silicon is to sinter the PZT to high density at sufficiently low temperature to avoid mechanical or chemical degradation of the silicon substrate. The goal of the present study is to develop and implement suitable electrodes and PZT

Ferroelectric thin films grown on tensile substrates: Renormalization of the Curie-Weiss law and apparent absence of ferroelectricity

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Proximity Induced Magnetic Anisotropy and Trefoil Fermiology in Monolayer FeCl 2 /Bi(111)

Semi-empirical universal model of heat capacity based on the Laplace distribution Напівемпірична універсальна модель теплоємності на основі розподілу Лапласа

Investigating Ultrafast Laser Driven Ferromagnetic Phase Nucleation Kinetics in FeRh using In-situ and Ultrafast Lorentz TEM

Chiral crossroads in Ho3ScO6 : Competing interactions on the maple-leaf lattice

Spin Caloritronics, origin and outlook

Asymmetry of collective excitations in electron- and hole-doped cuprate superconductors

Unusual dielectric behavior and domain structure in rhombohedral phase of BaTiO3 single crystals

Magnetic properties of the magnetoelectric compound Cu2OSeO3: Magnetization and Se-77 NMR study

Quench analysis of a high-current forced-flow HTS conductor model for fusion magnets

The realization and performance of vibration energy harvesting MEMS devices based on an epitaxial piezoelectric thin film

Ferroelectric transistors with improved characteristics at high temperature

Dielectric and acoustical high frequency characterisation of PZT thin films

Atomic-scale modelling of the Si(100)-SiO2 interface

Analysis of the non linear domain wall response in ferroelectric thin films

Shift of phase transition temperature in strontium titanate thin films

The remarkable difference between surface and step atoms in the magnetic anisotropy of two-dimensional nanostructures

Piezoelectric anisotropy-phase transition relations in perovskite single crystals

Carrier relaxation time divergence in single and double layer cuprates

Light controlled and probed ferromagnetism of (Cd,Mn)Te quantum wells

Processing and properties of screen-printed lead zirconate titanate piezoelectric thick films on electroded silicon