Reversible structural changes by electrostatic fields in strontium titanate at room temperature

Ti films of same thickness, and near normal deposition angle, and same deposition rate were deposited on glass substrates, at room temperature, under UHV conditions. Different annealing temperatures as 393K, 493K and 593K with uniform 8 cm3/sec, oxygen flow, were used for producing titanium oxide layers. Their nanostructures were determined by AFM and XRD methods. Roughness of the films changed due to annealing process. The gettering property of Ti and annealing temperature can play an important role in the nanostructure of the films.

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Infrared Transmittance of Strontium Titanate from Room Temperature to −180°C

Journal of the Optical Society of America ◽

10.1364/josa.51.001149 ◽

1961 ◽

Vol 51 (10) ◽

pp. 1149 ◽

Cited By ~ 6

Author(s):

Calvin D. Salzberg

Keyword(s):

Strontium Titanate ◽

Room Temperature ◽

Infrared Transmittance

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Thermo-Optical Properties of Perfluorinated Sulfonic Acid Membranes: An Investigation of Hydration Based on Absorption Spectra

Applied Spectroscopy ◽

10.1177/0003702817723649 ◽

2017 ◽

Vol 71 (11) ◽

pp. 2504-2511 ◽

Cited By ~ 1

Author(s):

Daniele T. Dias ◽

Guy Lopes ◽

Tales Ferreira ◽

Ivanir L. Oliveira ◽

Caroline D. Rosa

Keyword(s):

Sulfonic Acid ◽

Room Temperature ◽

Water Retention ◽

Structural Changes ◽

Optical Characterization ◽

Scanning Calorimetry ◽

Experimental Procedure ◽

Nafion Membranes ◽

Perfluorinated Sulfonic Acid

The Nafion membranes are widely used in electrochemical applications such as fuel cells, chlor-alkali cells, and actuators–sensors. In this work, the thermal-optical characterization of Nafion in acid form was performed by photoacoustic spectroscopy, thermogravimetry, and differential scanning calorimetry. In the experimental procedure three distinct hydration levels were considered: (1) pristine membrane (λ ≅ H2O/–SO3H ≅ 5.6); (2) swelling process (λ ≅ 17.4); and (3) drying at controlled room temperature after swelling process (λ ≅ 6.5). The discovered behaviors showed significant irreversible structural changes induced by water retention in the membrane. These structural changes depend on the water population present in the clusters and also affect the directional thermal diffusivity of the membrane irreversibly.

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Metallicity and Superconductivity in Doped Strontium Titanate

Annual Review of Condensed Matter Physics ◽

10.1146/annurev-conmatphys-031218-013144 ◽

2019 ◽

Vol 10 (1) ◽

pp. 25-44 ◽

Cited By ~ 22

Author(s):

Clément Collignon ◽

Xiao Lin ◽

Carl Willem Rischau ◽

Benoît Fauqué ◽

Kamran Behnia

Keyword(s):

Liquid Helium ◽

Free Path ◽

Coulomb Interaction ◽

Strontium Titanate ◽

Room Temperature ◽

Mean Free Path ◽

Helium Temperature ◽

Ongoing Research ◽

Low Concentrations ◽

Wide Gap

Strontium titanate is a wide-gap semiconductor avoiding a ferroelectric instability thanks to quantum fluctuations. This proximity leads to strong screening of static Coulomb interaction and paves the way for the emergence of a very dilute metal with extremely mobile carriers at liquid-helium temperature. Upon warming, mobility decreases by several orders of magnitude. Yet, metallicity persists above room temperature even when the apparent mean free path falls below the electron wavelength. The superconducting instability survives at exceptionally low concentrations and beyond the boundaries of Migdal–Eliashberg approximation. An intimate connection between dilute superconductivity and aborted ferroelectricity is widely suspected. In this review, we give a brief account of ongoing research on bulk strontium titanate as an insulator, a metal, and a superconductor.

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Room-temperature macromolecular crystallography using a micro-patterned silicon chip with minimal background scattering

Journal of Applied Crystallography ◽

10.1107/s1600576716006348 ◽

2016 ◽

Vol 49 (3) ◽

pp. 968-975 ◽

Cited By ~ 53

Author(s):

Philip Roedig ◽

Ramona Duman ◽

Juan Sanchez-Weatherby ◽

Ismo Vartiainen ◽

Anja Burkhardt ◽

...

Keyword(s):

Data Collection ◽

Room Temperature ◽

Structural Changes ◽

Crystalline Silicon ◽

Background Level ◽

Sample Holder ◽

Macromolecular Crystallography ◽

Recent Success ◽

Millisecond Range ◽

Humidified Air

Recent success at X-ray free-electron lasers has led to serial crystallography experiments staging a comeback at synchrotron sources as well. With crystal lifetimes typically in the millisecond range and the latest-generation detector technologies with high framing rates up to 1 kHz, fast sample exchange has become the bottleneck for such experiments. A micro-patterned chip has been developed from single-crystalline silicon, which acts as a sample holder for up to several thousand microcrystals at a very low background level. The crystals can be easily loaded onto the chip and excess mother liquor can be efficiently removed. Dehydration of the crystals is prevented by keeping them in a stream of humidified air during data collection. Further sealing of the sample holder, for example with Kapton, is not required. Room-temperature data collection from insulin crystals loaded onto the chip proves the applicability of the chip for macromolecular crystallography. Subsequent structure refinements reveal no radiation-damage-induced structural changes for insulin crystals up to a dose of 565.6 kGy, even though the total diffraction power of the crystals has on average decreased to 19.1% of its initial value for the same dose. A decay of the diffracting power by half is observed for a dose ofD1/2= 147.5 ± 19.1 kGy, which is about 1/300 of the dose before crystals show a similar decay at cryogenic temperatures.

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High Performance Flexible Organic Field-Effect Transistors with Barium Strontium Titanate Gate Dielectric Deposited at Room Temperature

ACS Applied Electronic Materials ◽

10.1021/acsaelm.9b00779 ◽

2020 ◽

Vol 2 (2) ◽

pp. 529-536

Author(s):

Vivek Raghuwanshi ◽

Deepak Bharti ◽

Ajay Kumar Mahato ◽

Amit Kumar Shringi ◽

Ishan Varun ◽

...

Keyword(s):

Strontium Titanate ◽

Barium Strontium Titanate ◽

Field Effect ◽

High Performance ◽

Room Temperature ◽

Gate Dielectric ◽

Field Effect Transistors ◽

Organic Field Effect Transistors ◽

Barium Strontium

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Metallicity without quasi-particles in room-temperature strontium titanate

npj Quantum Materials ◽

10.1038/s41535-017-0044-5 ◽

2017 ◽

Vol 2 (1) ◽

Cited By ~ 25

Author(s):

Xiao Lin ◽

Carl Willem Rischau ◽

Lisa Buchauer ◽

Alexandre Jaoui ◽

Benoît Fauqué ◽

...

Keyword(s):

Strontium Titanate ◽

Room Temperature

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Study on the Piezoelectric Behavior and Structural Changes of Strontium Doped PZT Ceramics

Materials Science Forum ◽

10.4028/www.scientific.net/msf.869.13 ◽

2016 ◽

Vol 869 ◽

pp. 13-18

Author(s):

Margarete Soares da Silva ◽

Lucas L. Silva ◽

Eliane F. Souza ◽

Elson Longo ◽

Maria A. Zaghete ◽

...

Keyword(s):

Lead Zirconate Titanate ◽

Room Temperature ◽

Structural Changes ◽

Piezoelectric Properties ◽

Lead Zirconate ◽

Strontium Content ◽

Pzt Ceramics ◽

Ceramic Samples ◽

Piezoelectric Behavior ◽

Piezoelectric Devices

Some piezoelectric properties of lead zirconate titanate PbZr0.53Ti0.47O3 ceramic samples sintered at 1100oC for 3 hours has been investigated in this work and compared to the strontium modification at 0.2, 0.4, and 0.6 mol%. Polarization versus Electric Field curve and d33 and Kp piezoelectric parameters was taken at room temperature in order to investigate the correlation with phase amount and lattice parameters of crystalline phases calculated through Rietveld refinement. The results indicated the lead substitution with 0.4 mol% of strontium enhances the d33 and Kp piezoelectric parameters, but there is no systematic variation of the piezoelectric properties with strontium content. By the other hand, tetragonal phase seems plays an important rule on piezoelectric devices operating near the room temperature and some correlations could be found.

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