TY - JOUR
KW - Thin films
KW - Thermal conductivity
KW - Crystallography
KW - Iron compounds
KW - Ferroelectric materials
KW - Bismuth compounds
KW - Energy conversion
KW - Ferroelectricity
KW - Lanthanum
KW - High Curie temperature
KW - Lanthanum substitution
KW - Paraelectric phase transition
KW - Pyroelectric coefficients
KW - Pyroelectric measurements
KW - Pyroelectric properties
KW - Reciprocal space mapping
KW - Structural phase transition
AU - L Zhang
AU - Y.-L Huang
AU - G Velarde
AU - A Ghosh
AU - S Pandya
AU - D Garcia
AU - Ramamoorthy Ramesh
AU - L.W Martin
AB - There is growing interest in the study of thin-film pyroelectric materials because of their potential for high performance thermal-energy conversion, thermal sensing, and beyond. Electrothermal susceptibilities, such as pyroelectricity, are known to be enhanced in proximity to polar instabilities, and this is conventionally accomplished by positioning the material close to a temperature-driven ferroelectric-to-paraelectric phase transition. The high Curie temperature (TC) for many ferroelectrics, however, limits the utility of these materials at room-temperature. Here, the nature of pyroelectric response in thin films of the widely studied multiferroic Bi1-xLaxFeO3 (x = 0-0.45) is probed. While BiFeO3 itself has a high TC, lanthanum substitution results in a chemically induced lowering of the ferroelectric-to-paraelectric and structural-phase transition. The effect of isovalent lanthanum substitution on the structural, dielectric, ferroelectric, and pyroelectric response is investigated using reciprocal-space-mapping studies; field-, frequency-, and temperature-dependent electrical measurements; and phase-sensitive pyroelectric measurements, respectively. While BiFeO3 itself has a rather small pyroelectric coefficient at room temperature (∼-40 μC/m2 K), 15% lanthanum substitution results in an enhancement of the pyroelectric coefficient by 100% which is found to arise from a systematic lowering of TC © 2019 Author(s).
BT - APL Materials
DO - 10.1063/1.5128413
LA - eng
M1 - 11
N1 - cited By 0
N2 - There is growing interest in the study of thin-film pyroelectric materials because of their potential for high performance thermal-energy conversion, thermal sensing, and beyond. Electrothermal susceptibilities, such as pyroelectricity, are known to be enhanced in proximity to polar instabilities, and this is conventionally accomplished by positioning the material close to a temperature-driven ferroelectric-to-paraelectric phase transition. The high Curie temperature (TC) for many ferroelectrics, however, limits the utility of these materials at room-temperature. Here, the nature of pyroelectric response in thin films of the widely studied multiferroic Bi1-xLaxFeO3 (x = 0-0.45) is probed. While BiFeO3 itself has a high TC, lanthanum substitution results in a chemically induced lowering of the ferroelectric-to-paraelectric and structural-phase transition. The effect of isovalent lanthanum substitution on the structural, dielectric, ferroelectric, and pyroelectric response is investigated using reciprocal-space-mapping studies; field-, frequency-, and temperature-dependent electrical measurements; and phase-sensitive pyroelectric measurements, respectively. While BiFeO3 itself has a rather small pyroelectric coefficient at room temperature (∼-40 μC/m2 K), 15% lanthanum substitution results in an enhancement of the pyroelectric coefficient by 100% which is found to arise from a systematic lowering of TC © 2019 Author(s).
PB - American Institute of Physics Inc.
PY - 2019
T2 - APL Materials
TI - Enhanced pyroelectric properties of Bi1-xLaxFeO3 thin films
VL - 7
SN - 2166532X
ER -