TUNABLE PHASE TRANSITION AND PHOTO-INDUCED RESISTANCE IN La0.8Ca0.2MnO3/FERROELECTRIC HETEROSTRUCTURES

Heterostructures of La 0.8 Ca 0.2 MnO 3 (LCMO)/ferroelectric were formed by growing a layer of perovskite manganite LCMO on the ferroelectric 0.67 Pb ( Mg 1/3 Nb 2/3) O 3-0.33 PbTiO 3 (PMN-PT) single crystals. Well tunable structural, magnetic, and transport properties were achieved by applying electric fields on the formed heterostructures. By varying electric fields biased on the PMN-PT, the metal–insulator transition and resistance could be modulated continuously and reversely. Field modulation of photo-induced resistance (PR) was also observed. In situ X-ray diffraction indicates that the variation of resistance and PR result from the induced strain due to the coaction ferroelectric polarization or converse piezoelectric effect. The variations of PR under different fields differ significantly when PMN-PT was in positively and negatively polarized states. Such observations could be explained based on the coaction of piezoelectric effect and ferroelectric-field polarization, which subsequently affect the lattice strain and density of charge carrier in the grown LCMO layer.

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Converse Piezoelectric Effect in Cellulose I Revealed by Wide-Angle X-ray Diffraction

Biomacromolecules ◽

10.1021/bm1000668 ◽

2010 ◽

Vol 11 (5) ◽

pp. 1281-1285 ◽

Cited By ~ 13

Author(s):

Wolfgang Gindl ◽

Gerhard Emsenhuber ◽

Johannes Plackner ◽

Johannes Konnerth ◽

Jozef Keckes

Keyword(s):

Piezoelectric Effect ◽

Wide Angle ◽

X Ray Diffraction ◽

Cellulose I ◽

X Ray ◽

Converse Piezoelectric Effect

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Sample chamber for synchrotron based in-situ X-ray diffraction experiments under electric fields and temperatures between 100 K and 1250 K

Journal of Synchrotron Radiation ◽

10.1107/s1600577520014344 ◽

2021 ◽

Vol 28 (1) ◽

pp. 158-168

Author(s):

Melanie Nentwich ◽

Tina Weigel ◽

Carsten Richter ◽

Hartmut Stöcker ◽

Erik Mehner ◽

...

Keyword(s):

Electric Fields ◽

Degrees Of Freedom ◽

X Ray Diffraction ◽

X Ray ◽

Heating And Cooling ◽

Hemispherical Dome ◽

Sample Chamber ◽

Overall Performance ◽

Scientific Questions

Many scientific questions require X-ray experiments conducted at varying temperatures, sometimes combined with the application of electric fields. Here, a customized sample chamber developed for beamlines P23 and P24 of PETRA III at DESY to suit these demands is presented. The chamber body consists mainly of standard vacuum parts housing the heater/cooler assembly supplying a temperature range of 100 K to 1250 K and an xyz manipulator holding an electric contact needle for electric measurements at both high voltage and low current. The chamber is closed by an exchangeable hemispherical dome offering all degrees of freedom for single-crystal experiments within one hemisphere of solid angle. The currently available dome materials (PC, PS, PEEK polymers) differ in their absorption and scattering characteristics, with PEEK providing the best overall performance. The article further describes heating and cooling capabilities, electric characteristics, and plans for future upgrades of the chamber. Examples of applications are discussed.

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Piezoelectric Properties of Pb1−xLax(Zr0.52Ti0.48)1−x/4O3 Thin Films Studied by In Situ X-ray Diffraction

Materials ◽

10.3390/ma13153338 ◽

2020 ◽

Vol 13 (15) ◽

pp. 3338

Author(s):

Thomas W. Cornelius ◽

Cristian Mocuta ◽

Stéphanie Escoubas ◽

Luiz R. M. Lima ◽

Eudes B. Araújo ◽

...

Keyword(s):

Thin Films ◽

Electric Fields ◽

Lead Zirconate Titanate ◽

Piezoelectric Properties ◽

Lead Zirconate ◽

X Ray Diffraction ◽

X Ray ◽

Ac Electric Fields ◽

Zirconate Titanate

The piezoelectric properties of lanthanum-modified lead zirconate titanate Pb1−xLax(Zr0.52Ti0.48)1−x/4O3 thin films, with x = 0, 3 and 12 mol% La, were studied by in situ synchrotron X-ray diffraction under direct (DC) and alternating (AC) electric fields, with AC frequencies covering more than four orders of magnitude. The Bragg reflections for thin films with low lanthanum concentration exhibit a double-peak structure, indicating two contributions, whereas thin films with 12% La possess a well-defined Bragg peak with a single component. In addition, built-in electric fields are revealed for low La concentrations, while they are absent for thin films with 12% of La. For static and low frequency AC electric fields, all lanthanum-modified lead zirconate titanate thin films exhibit butterfly loops, whereas linear piezoelectric behavior is found for AC frequencies larger than 1 Hz.

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Domain wall motion and electromechanical strain in lead-free piezoelectrics: Insight from the model system (1 − x)Ba(Zr0.2Ti0.8)O3–x(Ba0.7Ca0.3)TiO3 using in situ high-energy X-ray diffraction during application of electric fields

Journal of Applied Physics ◽

10.1063/1.4870934 ◽

2014 ◽

Vol 115 (14) ◽

pp. 144104 ◽

Cited By ~ 60

Author(s):

Goknur Tutuncu ◽

Binzhi Li ◽

Keith Bowman ◽

Jacob L. Jones

Keyword(s):

Electric Fields ◽

Wall Motion ◽

Domain Wall Motion ◽

High Energy ◽

Model System ◽

Lead Free ◽

X Ray Diffraction ◽

X Ray ◽

System 1

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The Use of Advanced Analytical Techniques for Characterization of the Chemical, Physical, and Crystallographic Nature of a Surface

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100071107 ◽

1973 ◽

Vol 31 ◽

pp. 132-133 ◽

Cited By ~ 1

Author(s):

R. E. Herfert

Keyword(s):

Surface Characterization ◽

Analytical Techniques ◽

X Ray Diffraction ◽

Depth Of Penetration ◽

X Ray ◽

The Past ◽

Transmission Electron ◽

Scanning Electron

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.

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