Reversible and irreversible processes in donor-doped Pb(Zr,Ti)O3

Bolten, D.; Böttger, U.; Schneller, Theodor; Grossmann, M.; Lohse, O.; Waser, Rainer

doi:10.1063/1.1331353

Cited by 73 publications

(42 citation statements)

References 13 publications

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“…4,5 Such behavior may cause several effects on the dielectric behavior through interaction with domain walls. 6,7 Recently, it was found that in sintering of Y 2 O 3 -doped BTO with Y 2 O 3 higher than 0.80 mol %, presumably exceeded the solid solubility of Y 2 O 3 in BTO, is improved by both enhanced densification ͑by solid-solution defect͒ and suppressed coarsening ͑by second-phase pinning͒. 8 These results demonstrate the performance of our capacitors for future piezoelectric resonators consuming low energy levels at low phase transition temperature.…”

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confidence: 59%

Strain and vacancy cluster behavior of vanadium and tungsten-doped Ba[Zr0.10Ti0.90]O3 ceramics

Moura

Simões

Cavalcante

et al. 2008

Applied Physics Letters

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Strain and vacancy clusters behavior of polycrystalline vanadium (V) and tungsten (W)-doped Ba[Zr0.10Ti0.90]O3, (BZT:2%V) and (BZT:2%W) ceramics obtained by the mixed oxide method was evaluated. Substitution of V and W reduces the distortion of octahedral clusters, decreasing the Raman modes. Electron paramagnetic resonance data indicate that the addition of dopants leads to defects and symmetry changes in the BZT lattice. Remnant polarization and coercive field are affected by V and W substitution due the electron-relaxation mode. The unipolar strain E curves as a function of electric field reach its maximum value for BZT:2%V and BZT:2%W ceramics.

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mentioning

confidence: 59%

Strain and vacancy cluster behavior of vanadium and tungsten-doped Ba[Zr0.10Ti0.90]O3 ceramics

Moura

Simões

Cavalcante

et al. 2008

Applied Physics Letters

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“…Between A and B the process is fully reversible, while between B and E irreversibility is involved. Bolten et al 16 pointed out that in the ferroelectric P-E loops, the reversible part can be described by a straight line without any hysteretic heat loss since the contribution mainly arises from the ionic and electronic polarization. This straight line should cross through the center of the hysteresis.…”

Section: Arxiv:160803401v3 [Cond-matmtrl-sci] 30 Aug 2016mentioning

confidence: 99%

Optimized electrocaloric effect by field reversal: Analytical model

Novak

Albe

et al. 2016

Applied Physics Letters

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Application of a negative field on a positively poled ferroelectric sample can enhance the electrocaloric cooling and appears as a promising method to optimize the electrocaloric cycle. Experimental measurements show that the maximal cooling does not appear at the zero-polarization point, but around the shoulder of the P-E loop. This phenomenon cannot be explained by the theory based on the constant total entropy assumption under adiabatic condition. In fact, adiabatic condition does not imply constant total entropy when irreversibility is involved. A direct entropy analysis approach based on work loss is proposed in this work, which takes the entropy contribution of the irreversible process into account. The optimal reversed field determined by this approach agrees with the experimental observations. This study signifies the importance of considering the irreversible process in the electrocaloric cycles.The electrocaloric (EC) effect shows great application potential in the technology of solid state refrigeration. 1-3Even though much effort has been made to explore material candidates with large EC effect and device concepts, there are few work concerning the optimization of electrocaloric cycle. In a conventional EC cycle of a solid refrigerant, the cooling effect is obtained simply by removing the previously applied electric field. Using direct heat flux calorimetry on poly(vinylidene fuoridetride-trifuoroethylene) films, Basso et al. 4 demonstrated that the electrocaloric cooling can be doubled if a negative electric field to a positively poled sample is applied. The EC hysteresis of ferroelectric ceramics measured by Thacher et al.5 indicated also that a reversed electric field can increase the cooling effect of ferroelectric ceramics. In the authors' previous work, 6 experimental and numerical studies were carried in PMN-29PT and BaTiO 3 , which demonstrated that there exists an optimal reversed electric field, corresponding to a position around the shoulder of the dielectric hysteresis. At this point, the EC cooling effect reaches its maximum (also see Fig. 1). This phenomenon was also observed in Ref. 4. It is of scientific and engineering importance to deter- mine and understand this optimal reversed electric field. In the literature, as reviewed in Ref. 7, the EC cycle is considered to be reversible, with constant total entropy under the adiabatic condition. This assumption leads to the conclusion that the maximal cooling takes place at the zero polarization point, since at this point the dipolar entropy takes maximum (see Model I). This conclusion deviates obviously from the experimental observations. In fact, the total entropy S total should satisfy:where S dip and S vib are the dipolar and the vibrational entropy, respectively. In the case of applying a reversed electric field, the irreversible contribution becomes considerable. In other words, to correctly determine the optimal reversed electric field, the change of the total entropy induced by the work loss W loss due to the irreversible process s...

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“…The Rayleigh law has been widely observed in ferromagnetic materials [2], but also in ferroelectric ceramics [3,4]. The current theoretical interpretation of this law is based on a 1942 paper by Néel [5], who derived the law formulating the magnetization process as the dynamics of a point (i.e.…”

Section: Introductionmentioning

confidence: 99%

Low-field hysteresis in disordered ferromagnets

et al. 2002

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We analyze low field hysteresis close to the demagnetized state in disordered ferromagnets using the zero temperature random-field Ising model. We solve the demagnetization process exactly in one dimension and derive the Rayleigh law of hysteresis. The initial susceptibility a and the hysteretic coefficient b display a peak as a function of the disorder width. This behavior is confirmed by numerical simulations d = 2, 3 showing that in limit of weak disorder demagnetization is not possible and the Rayleigh law is not defined. These results are in agreement with experimental observations on nanocrystalline magnetic materials.

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Reversible and irreversible processes in donor-doped Pb(Zr,Ti)O3

Cited by 73 publications

References 13 publications

Strain and vacancy cluster behavior of vanadium and tungsten-doped Ba[Zr0.10Ti0.90]O3 ceramics

Strain and vacancy cluster behavior of vanadium and tungsten-doped Ba[Zr0.10Ti0.90]O3 ceramics

Optimized electrocaloric effect by field reversal: Analytical model

Low-field hysteresis in disordered ferromagnets

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