Search results for "ROV"

Provincia de Valencia

Llegenda. - Relleu representat per corbes de nivell. - Representació dels fars Edició especial d'agost de 1938 del mapa editat pel Ministerio de Obras Públicas el 1935

Introducing a sensemaking perspective to the service experience

2021

PurposeMost recent service experience research considers customers as sensemakers and sensemaking as a focal process in experience construction. Despite this, the sensemaking theory engendered in organization studies has not been applied in the quest for an in-depth understanding of the service experience. This study introduces a sensemaking perspective to the service experience and develops a conceptualization of how customers construct their experiences cognitively through sensemaking.Design/methodology/approachThe service experience literature is dominated by a focus on firms implementing service experiences for customers. This study, in contrast, investigates service experience and its …

Giant Anomalous Nernst Effect in Noncollinear Antiferromagnetic Mn-based Antiperovskite Nitrides

2020

The anomalous Nernst effect (ANE) - the generation of a transverse electric voltage by a longitudinal heat current in conducting ferromagnets or antiferromagnets - is an appealing approach for thermoelectric power generation in spin caloritronics. The ANE in antiferromagnets is particularly convenient for the fabrication of highly efficient and densely integrated thermopiles as lateral configurations of thermoelectric modules increase the coverage of heat source without suffering from the stray fields that are intrinsic to ferromagnets. In this work, using first-principles calculations together with a group theory analysis, we systematically investigate the spin order-dependent ANE in nonco…

Tetragonal tungsten bronze compounds: relaxor versus mixed ferroelectric-dipole glass behavior.

2011

We demonstrate that recent experimental data (E. Castel et al J.Phys. Cond. Mat. {\bf 21} (2009), 452201) on tungsten bronze compound (TBC) Ba$_2$Pr$_x$Nd$_{1-x}$FeNb$_4$O$_{15}$ can be well explained in our model predicting a crossover from ferroelectric ($x=0$) to orientational (dipole) glass ($x=1$), rather then relaxor, behavior. We show, that since a "classical" perovskite relaxor like Pb(Mn$_{1/3}$ Nb$_{2/3}$)O$_3$ is never a ferroelectric, the presence of ferroelectric hysteresis loops in TBC shows that this substance actually transits from ferroelectric to orientational glass phase with $x$ growth. To describe the above crossover theoretically, we use the simple replica-symmetric so…

Manifestation of dipole-induced disorder in self-assembly of ferroelectric and ferromagnetic nanocubes

2019

The authors thank Marjeta Maˇcek Kržmanc for many useful discussions. The financial support of M-ERA.NET Project Har-vEnPiez (Innovative nano-materials and architectures for integrated piezoelectric energy harvesting applications) is gratefully acknowledged. D.Z. acknowledges the support of the postdoctoral research program at the University of Latvia (Project No. 1.1.1.2/VIAA/1/16/072). The computing time of the LASC cluster was provided by the Institute of Solid State Physics (ISSP).

Electronic structure of two crystallographic forms ofBaRuO3

2000

Electronic structure calculations have been performed to explain the difference in the electronic properties of two crystallographic forms of ${\mathrm{BaRuO}}_{3}.$ The calculations can explain the qualitatively different resistivities of isoelectronic $4H$- and $9R$-${\mathrm{BaRuO}}_{3}$ below 100 K. The difference in symmetry between the hexagonal four-layer ${\mathrm{BaRuO}}_{3}$ and the rhombohedral nine-layer compound allows the formation of a gap for the later. The electronic structure of these hexagonal perovskites is compared with the more familiar cubic perovskite ${\mathrm{CaRuO}}_{3}.$

Calculations of radiation-induced point defects, polarons and excitons in ferroelectric perovskites

2002

Abstract We review results of our recent large-scale computer simulations of radiation-induced point defects, excitons and polarons in ABO3 perovskite crystals, focusing mostly on KNbO3 and KTaO3 as representative examples. We have calculated the atomic and electronic structure of defects, their optical absorption, defect-induced electron density redistribution, and activation energies for defect migration. The majority of our results were obtained using the quantum-chemical method of the intermediate neglect of differential overlap (INDO) based on the Hartree–Fock formalism, as well as the shell model (SM). The main findings are compared with those obtained by means of ab initio density fu…

Large scale computer modelling of point defects in ABO 3 perovskites

2005

We present results for basic intrinsic defects: F-type electron centers, free and bound electron and hole polarons in ABO3 perovskites. Both one-site (atomic) and two-site (molecular) hole polarons are expected to coexist, characterized by close absorption energies. Shell Model (SM) and intermediate neglect of differential overlap (INDO) calculations of the F center diffusion indicate that the relevant activation energy is quite low, ca. 0.8 eV. Further INDO calculations support the existence of self-trapped electron polarons in PbTiO3, BaTiO3, KNbO3, and KTaO3 crystals. The relevant lattice relaxation energies are typically 0.2 eV, whereas the optical absorption energies are around 0.8 eV.…

Magnetic field tuning of the smart materials domain structure

1998

The investigation of the behavior of the ferroelectric phase transition with magnetic filed tuning and concentration change is highly attractive owing to the possibility to prepare alloying samples and to predict theoretically the parameters of the magnetic field and concentration response at relatively small concentrations. These parameters may be extracted from the equation of states of the perovskite under investigation in the assumption of the linear response. The study of the movement of the paraelectric - ferroelectric interphase boundary in (Ba,Sr)TiO 3 with concentration change and in constant magnetic fields is provided in the framework of the mean-field theory. The analytical solu…

First-Principles Simulation of Substitutional Defects in Perovskites

2000

The results of supercell calculations of electronic structure and related properties of substitutional impurities in perovskite oxides KNbO3 and KTaO3 are discussed. For Fe impurities in KNbO3, the results obtained in the local density approximation (LDA) and in the LDA+U approach (that allows an ad hoc treatment of nonlocality in exchange-correlation) are compared, and different impurity charge configurations are discussed. The study of off-centre Li defects in incipient ferroelectric KTaO3 have been done by the appropriately parametrized Intermediate Neglect of Differential Overlap (INDO) method. The interaction energies of two off-centre impurities in different relative configurations ar…