Showing papers on "Ferroelectric ceramics published in 1971"
TL;DR: In this paper, transparent ferroelectric ceramic materials suitable for a variety of electrooptic applications were found in the quaternary (Pb,La,Zr,Ti)O3 system.
Abstract: Transparent ferroelectric ceramic materials suitable for a variety of electrooptic applications were found in the quaternary (Pb,La)(Zr,Ti)O3 system. These PLZT materials are prepared from mixed oxides and hot-pressed typically at 1100°C for 16 h at 2000 psi. Modifying the lead zirconate-titanate system with lanthana linearly reduces the Curie point with increasing lanthana. Transmission measurements in the visible and infrared show that these materials exhibit a nearly constant response from the absorption edge of 0.37 μ to ∼6 μm. The highest transmission values, essentially 100% (neglecting reflection losses of ∼18%) for thin polished plates, were noted for compositions containing 8 at.% La or more. Specific compositions within the system display electrooptic memory or conventional linear or quadratic electrooptic effects; on the basis of the magnitude of the electrooptic effects, they compare quite favorably with single crystals.
1,002 citations
TL;DR: In this paper, it was shown that impurities introduced by thermal diffusion can improve propagation properties of surface waves excited on unpolarized ceramic plates using an interdigital arrangement of electrodes.
Abstract: It is shown that impurities introduced by thermal diffusion can improve propagation properties of surface waves excited on unpolarized ceramic plates using an interdigital arrangement of electrodes. In BaTiO3 ceramics, CO2O3 reduces the attenuation constant of surface waves to one‐half the values obtained with specimens with no added impurities. In the most favorable case, the output voltage due to the surface waves increased by a factor of 3.
3 citations
01 Mar 1971
TL;DR: The electrooptic properties of hot-pressed lead zirconate titanate (PLZT) ceramics and their applications are reviewed in this paper, where the authors show that PLZT can be used for information storage and display devices.
Abstract: The electrooptic properties of hot-pressed lead zirconate titanate ceramics and their applications are reviewed. Coarse-grained, bismuth-doped ceramics with average grain size greater than 2 ώm have light scattering properties that can be varied by switching the orientation of the ferroelectric polarization. Fine-grained bismuth-or lanthanum-doped ceramics have an effective birefringence that can be varied either by applying an external electric field (conventional electrooptic effect) or by partially switching the remanent polarization (electrooptic memory effect). Ba, Sn, or La modifications of the lead zirconate titanate system produce materials with improved switching characteristics and electrooptic effects similar to those of fine-grained bismuth-or lanthanum-doped ceramics. Lanthanum modified lead zirconate titanate (PLZT) is significantly more transparent than other electrooptic ceramics. The PLZT system includes materials with electrooptic memory and either linear or quadratic electrooptic effects. The electrooptic properties of modified lead zirconate titanate ceramics, especially PLZT, combined with localized switching and modulation capabilities are particularly suitable for information storage and display devices.
2 citations
01 Jan 1971
TL;DR: In the last few years Land and his coworkers at the Sandia Corporation Laboratories have demonstrated that electrically-controlled birefringence and light scattering can be realized in lead-zirconate-titanate (PZT) ferroelectric ceramics.
Abstract: In the last few years Land and his coworkers at the Sandia Corporation Laboratories have demonstrated that electrically-controlled birefringence and light scattering can be realized in lead-zirconate-titanate (PZT) ferroelectric ceramics.1–7 The electrically controlled birefringence is related to the change induced by an electric field in the statistically-averaged birefringence of the crystallites comprising the ceramic. The electrically controlled light scattering has been interpreted by Nettleton in terms of domain wall displacement.8 By appropriate choice of modified PZT ceramics and device configuration, it has been possible to devise electrically controlled light shutters, spectral filters, optical memories, light modulators, variable contrast black-and-white displays and multicolor displays.1–4 Subsequently other laboratories have investigated various aspects of image storage and display based on the electrically-controlled birefringence in modified PZT ferroelectric ceramics.9–12 Meanwhile Heartling at Sandia was able to improve the optical transparency of PZT by the addition of various modifiers, culminating in his preparation of the first optically transparent ferroelectric ceramic, lead lanthanum zirconate titanate (PLZT).13–16 The development of the transparent PLZT may well enable the electrically controlled birefringence in these ferroelectric ceramics to realize practical application.
2 citations