Wide Electrocaloric Temperature Range Induced by Ferroelectric to Antiferroelectric Phase Transition

The ferroelectric (FE) to antiferroelectric (AFE) phase transition tuning the temperature range of electrocaloric (EC) effects was investigated using phenomenological Landau–Devonshire theory. Contrary to ferroelectric to paraelectric (PE) phase transitions for electrocaloric effects, the ferroelectric to antiferroelectric phase transition was adopted to obtain large entropy changes under an applied electric field in a Sm-doping BiFeO3 system. In addition, the doping composition and hydrostatic pressure was observed to tune the ferroelectricantiferroelectric–paraelectric phase transition temperatures and broaden the operating temperature range of electrocaloric effects. The optimal wide temperature range of ~78 K was observed at 3 GPa compressive hydrostatic pressures and 0.05 Sm-doping BiFeO3. The present study paves the way to designing high efficiency cooling devices with larger operating temperature spans.

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Surface and Size Effects in TGS, NaNO2, and DKDP Nanocrystals

MRS Proceedings ◽

10.1557/proc-655-cc10.12.1 ◽

2000 ◽

Vol 655 ◽

Author(s):

Juan D. Romero ◽

Luis F. Fonseca ◽

Rafael Ramos ◽

Manuel I. Marqués ◽

Julio A. Gonzalo

Keyword(s):

Phase Transition ◽

Monte Carlo ◽

Ising Model ◽

Monte Carlo Simulations ◽

Size Effects ◽

Paraelectric Phase ◽

Paraelectric Phase Transition ◽

Model Hamiltonian ◽

Phase Transition Temperatures ◽

Polarization Temperature

AbstractMonte Carlo simulations of some typical order-disorder ferroelectrics such as TGS, NaNO2 and DKDP nanocrystals were studied using a Transverse Ising Model Hamiltonian with four-spins interactions. The microscopic parameters corresponding to this Hamiltonian were adjusted to fit the experimental polarization-temperature curves for each one of the materials in the bulk phase. Then the dependences of the ferroelectric-paraelectric phase transition temperatures, Tc, on the sizes of those crystals were studied with Monte Carlo simulations of the order-disorder system. We report a weak dependence of Tc on the size of the crystal (d) for these materials above d∼6nm. The addition of surface effects showed that the expected lowtemperature shift of Tc due to size effects, can be reverted.

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Ferroelectric-paraelectric Phase Transition Temperatures of an Array of Nanorods (nanocones) with a Gaussian Size Distribution

10.1557/proc-1110-c09-13 ◽

2008 ◽

Author(s):

Gunnar Suchaneck ◽

Pavlo I. Bykov ◽

Lubomir Jastrabik ◽

Igor P. Bykov ◽

Gerlald Gerlach

Keyword(s):

Phase Transition ◽

Size Distribution ◽

Paraelectric Phase ◽

Transition Temperatures ◽

Paraelectric Phase Transition ◽

Phase Transition Temperatures

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Low-energy ferroelectric–paraelectric phase transitions of three-dimensional A(II)B(I)X3-type perovskite ferroelectrics: How to realize high phase transition temperatures

APL Materials ◽

10.1063/5.0035199 ◽

2021 ◽

Vol 9 (1) ◽

pp. 010704

Author(s):

Jie Bie ◽

Wei Fa ◽

Shuang Chen

Keyword(s):

Phase Transition ◽

Phase Transitions ◽

Paraelectric Phase ◽

Three Dimensional ◽

Low Energy ◽

Transition Temperatures ◽

Phase Transition Temperatures ◽

High Phase

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Ionic Liquids as Wide Operating Temperature Range Lubricant

New Technologies, Development and Application III - Lecture Notes in Networks and Systems ◽

10.1007/978-3-030-46817-0_40 ◽

2020 ◽

pp. 348-359

Author(s):

Darko Lovrec ◽

Vito Tič

Keyword(s):

Ionic Liquids ◽

Operating Temperature ◽

Temperature Range ◽

Wide Operating ◽

Operating Temperature Range

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Reference Voltage Supply Source with Expanded Operating Temperature Range

KnE Engineering ◽

10.18502/keg.v3i6.2995 ◽

2018 ◽

Vol 3 (6) ◽

pp. 213

Author(s):

A V Popova ◽

V M Kisel ◽

A Yu Malyavina ◽

A S Bakerenkov ◽

Yu R Shaltaeva

Keyword(s):

Operating Temperature ◽

Reference Voltage ◽

Supply Source ◽

Voltage Supply ◽

Temperature Range ◽

Operating Temperature Range

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Research on Nozzle Array Structure Fluidic Gyroscope Zero Temperature Compensation

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.542-543.631 ◽

2012 ◽

Vol 542-543 ◽

pp. 631-634

Author(s):

Xing Wang ◽

Lin Hua Piao ◽

Quan Gang Yu

Keyword(s):

Temperature Compensation ◽

Operating Temperature ◽

Temperature Characteristic ◽

Zero Drift ◽

Zero Temperature ◽

Single Chip ◽

Temperature Range ◽

Compensation Methods ◽

Array Structure ◽

Operating Temperature Range

The nozzle array structure fluidic gyroscope’s zero temperature compensation was researched. The fluidic gyroscope’s temperature characteristic was analyzed in the sensitive element and two zero temperature compensation methods were compared. Then, the software compensation method was used, which based on the Single chip microcomputer technology and realized temperature compensation for the gyroscope output signal. The results show that after the compensation, the gyroscope’s zero drift decreases from ≤1.3mV/°C to ≤0.1mV/°C and operating temperature range increases from normal temperature to -40°C~+60°C. Therefore, the fluidic gyroscope has the advantage of low zero drift and width operating temperature range after the zero temperature compensation, which provides the convenience for the production and application.

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