相关论文: Strain gradient induced polarization in SrTiO3 sin…
Ferroic domain walls could play an important role in microelectronics, given their nanometric size and often distinct functional properties. Until now, devices and device concepts were mostly based on mobile domain walls in ferromagnetic…
PbZrxTi1-xO3 (PZT) is one of the technologically most important ferroelectric materials. Bulk single-domain single crystals of PZT have never been synthesized for a significant compositional range across the solid-solution phase diagram.…
The flexoelectric behaviors of solids under high strain gradient can be distinct from that under low strain gradient. Using the generalized Bloch theorem, we investigate theoretically the transversal flexoelectric effects in bent MgO…
Highly-crystalline ferroelectric oxides integrated on Si hold great promise for energy-efficient memory and logic technologies. Exploiting epitaxial strain engineering in these materials is, however, severely hampered on Si, where the large…
The origin of the functional properties of complex oxide superlattices can be resolved using time-resolved synchrotron x-ray diffraction into contributions from the component layers making up the repeating unit. The CaTiO3 layers of a…
The theories of flexoelectricity and that of nonlocal elasticity are closely related, and are often considered together when modeling strain-gradient effects in solids. Here I show, based on a first-principles lattice-dynamical analysis,…
We investigated the ferroelectric properties of strontium titanate (STO) thin films deposited on SrTiO3 (001) substrate with SrRuO3 electrodes. The STO layer was grown coherently on the SrTiO3 substrate without in-plane lattice relaxation,…
The nature of the "failed" ferroelectric transition in SrTiO3 has been a long-standing puzzle in condensed matter physics. A compelling explanation is the competition between ferroelectricity and an instability with a mesoscopic modulation…
We report a systematic study of the structure, electric and magnetic properties of Ca$_3$Co$_{2-x}$Mn$_x$O$_6$ single crystals with $x =$ 0.72 and 0.26. The DC and AC magnetic susceptibilities display anomalies with characteristic of the…
Flexoelectricity is a type of ubiquitous and prominent electromechanical coupling, pertaining to the response of electrical polarization to mechanical strain gradients while not restricted to the symmetry of materials. However, large…
Materials tuned to the neighbourhood of a zero temperature phase transition often show the emergence of novel quantum phenomena. Much of the effort to study these new effects, like the breakdown of the conventional Fermi-liquid theory of…
Flexoelectricity, an electromechanical coupling between strain gradient and polarization, offers a promising dimension to enrich silicon-based devices. Although the flexoelectricity of silicon is known, some fundamental aspects remain…
Conventional perovskite-type ferroelectrics are based on octahedral units of oxygen, and often comprise toxic Pb to achieve robust ferroelectricity. Here, we report the ferroelectricity in a silicate-based compound, Bi2SiO5 (BSO), induced…
SrTiO3 is a textbook quantum paraelectric, with ferroelectricity purportedly suppressed by quantum fluctuations of ionic positions down to the lowest temperatures. The precise real space structure of SrTiO3 at low temperature, however, has…
We analyze the electromechanical response of the 180 degree ferroelectric domain wall in tetragonal PbTiO3 by combining first-principles calculations with a Landau-Ginzburg-Devonshire (LGD) description. Using regular multidomain structures…
Detailed Raman spectroscopy studies on polycrystalline Sr1-xPrxTiO3 (x=0.01, 0.025, 0.05, 0.075, 0.09, 0.13, 0.15, 0.17) samples are reported elucidating the microscopic mechanism of relaxor ferroelectrics. The polar mode was observed upto…
Pure NaNbO$_{3}$ is an antiferroelectric material at room temperature that irreversibly transforms to a ferroelectric polar state when subjected to an external electrical field or lattice strain. Experimentally, it has been observed that…
The emerging interest in two-dimensional electron gases (2DEGs), formed at interfaces between two insulating oxide perovskites poses crucial fundamental question in view of future electronic devices. In the framework of density-functional…
The crystal structure of BiFeO3/BaxSr1-xTiO3 (BFO/BST) heterostructures with x = 0.2, 0.6 and 0.8, grown on single-crystal MgO (001) substrate was investigated by x-ray diffraction and Raman spectroscopy in order to determine the influence…
X-ray diffraction, dynamical mechanical analysis and infrared reflectivity studies revealed an antiferrodistortive phase transition in EuTiO3 ceramics. Near 300K the perovskite structure changes from cubic Pm-3m to tetragonal I4/mcm due to…