Phase front and domains during the paraelectric-ferroelectric transition in<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">KD</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub></mml:mrow><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">PO</mml:mi></mml:mrow><mml:mrow><mml:mn>4</mml:mn></mml:mrow></mml:msub></mml:mrow><mml:mo>:</mml:mo></mml:math>Optical observation and dielectric contributions

Bornarel, Jean; Cach, R.

doi:10.1103/physrevb.60.3806

Cited by 15 publications

(9 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the ferroelectric phase the dielectric permittivity remains in a plateau, indicating also the large domain wall contribution to the dielectric permittivity, but the maximum of permittivity decreases with the applied electric field. It has been previously reported that the maximum value of dielectric permittivity is due to the contribution of the domain wall [25]; under an electric field the sample becomes close to a monodomain state, so the number of domain walls decreases, and also the dielectric permittivity. Nevertheless, the behaviour at the transition temperature is different for 0 and 100 V cm −1 -discontinuous transition-than for 400 V cm −1 -close-to-critical-point transition-and 1000 V cm −1 -continuous transition.…”

Section: Dielectric Measurementsmentioning

confidence: 98%

The influence of an electric field on the latent heat of the ferroelectric phase transition in KDP

Sánchez

Martín‐Olalla

Gallardo

et al. 2005

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

The specific heat, heat flux (DTA trace) and dielectric constant of KDP ferroelectric crystal have been measured simultaneously for various electric fields with a conduction calorimeter. The specific heat presents a strong anomaly but these simultaneous measurements allow us to evaluate the latent heat accurately. Latent heat decreases with field and the value of critical electric field -that where latent heat disappears-is estimated to be (0.44 ± 0.03) kV cm −1 . Incidentally, we have measured simultaneously the dielectric permittivity which suggests that latent heat is developed as domains are growing.

show abstract

Section: Dielectric Measurementsmentioning

confidence: 98%

The influence of an electric field on the latent heat of the ferroelectric phase transition in KDP

Sánchez

Martín‐Olalla

Gallardo

et al. 2005

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

show abstract

“…Because of their small size, the initial metastable structures are generally observed by transmission electron microscopy (TEM) or diffuse x-ray scattering. In transparent crystals with weak first order transition, larger interfacial structures may be observed by optical measurements [3]. The ÿ transition of quartz deserves special attention due to many important results obtained during a century of research [4].…”

mentioning

confidence: 99%

Origin of the Opalescence at theα−βTransition of Quartz: Role of the Incommensurate Phase Studied by Synchrotron Radiation

Dolino¹,

Bastie²,

Capelle³

et al. 2005

Phys. Rev. Lett.

View full text Add to dashboard Cite

The origin of the light scattering observed at the alpha-beta transition of quartz is still a subject of controversy. We present structural studies performed during the coexistence of the alpha and the intermediate incommensurate (inc) phases using simultaneously synchrotron x-ray diffraction and optical techniques. The small and large angle light scatterings are due, respectively, to the orientation domains of the 3q inc phase and to the alpha phase twins revealed by diffuse x-ray scattering. In the vicinity of the interphase boundary, the two light scattering regions, both with perturbed properties, form a complex multiscale structure.

show abstract

“…It has been shown that the behaviour of the dielectric constant in a first-order phase transition provides information about the kinetics of the phase transition [16][17][18][19]. Let us consider the paraelectric-ferroelectric phase transition.…”

mentioning

confidence: 99%

Phase coexistence in highly deuterated ferroelectric triglycine selenate: Landau description

2006

View full text Add to dashboard Cite

Abstract. -The phase transition in a 90% deuterated sample of TGSe has been investigated by calorimetric and dielectric measurements. As a consequence of the presence of an internal crack in the sample, the transition takes place in two stages separated by an interval where the paraelectric and the ferroelectric phases coexist without latent heat contribution. From the latent heat, the specific heat excess and the Curie law for the dielectric constant, it is shown that the transition follows a 2-4-6 Landau potential, whose coefficients are determined. This potential describes completely all the data, including those corresponding to the coexistence interval.Introduction. -Compositional changes affect very significantly most ferroelectric phase transitions and their effects are particularly important if the transition is close enough to a tricritical point, so that the first-or second-order nature could be modified. Triglycine selenate [(NH 2 CH 2 COOH) 3 H 2 SeO 4 ], here-after TGSe, is a well-known uniaxial ferroelectric material belonging to the triglycine sulphate (TGS) family. It undergoes a typical order-disorder phase transition at about T ∼ 295 K, the space group of the lower-temperature phase being P2 1 and that of the higher-temperature phase P2 1 /m. [1,2]. Recently, we performed a calorimetric study on the phase transition showing that the specific heat of the ferroelectric phase follows a classical tricritical Landau potential whose coefficients have been determined [3].The effect of deuteration on the dielectric properties of phase transition in TGSe has been previously investigated [4][5][6]. It has been found that the thermal hysteresis as determined from dielectric-constant measurements increases when the deuteration increases, which indicates that the transition becomes first order.Concerning the thermal properties of partially deuterated TGSe, the specific heat and the latent heat of a 62% deuterated sample and under the effect of γ-irradiation have been measured [7,8]. The specific heat behaviour was found to follow the predictions of a 2-4-6 Landau potential and the latent heat was evaluated to be 168 J mol −1 . In a very recent paper [9], we reported a preliminary analysis of the specific heat and latent heat of a 90% deuterated sample of TGSe using the technique "Square Modulated Differential Thermal Analysis" (SMDTA) [10], which has been proved to be very useful in the investigation

show abstract

Phase front and domains during the paraelectric-ferroelectric transition inKD2PO4:Optical observation and dielectric contributions

Cited by 15 publications

References 29 publications

The influence of an electric field on the latent heat of the ferroelectric phase transition in KDP

The influence of an electric field on the latent heat of the ferroelectric phase transition in KDP

Origin of the Opalescence at theα−βTransition of Quartz: Role of the Incommensurate Phase Studied by Synchrotron Radiation

Phase coexistence in highly deuterated ferroelectric triglycine selenate: Landau description

Contact Info

Product

Resources

About