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A series of In2O3 semiconducting thin films were grown on the ferroelectric 0.71Pb(Mg1/3Nb2/3)O3–0.29PbTiO3(111) (PMN–PT) single-crystal substrates in the form of ferroelectric field effect transistor (FeFET) devices by the pulsed laser deposition. The effects of substrate temperature and oxygen pressure on the structural and electrical properties of the In2O3 films are investigated. We find that the substrate temperature and oxygen pressure have great impact on the performance of the In2O3/PMN–PT FeFETs whose channel resistance could be tuned in a nonvolatile and reversible manner via the ferroelectric polarization switching in the PMN–PT layer. In particular, a significant resistance change of 144% and a carrier density change of 92% are achieved at room temperature for the In2O3 film deposited at 600 °C and 2 Pa oxygen pressure. Our results provide useful deposition parameters for growing epitaxial In2O3 thin films on large lattice-mismatched perovskite substrates and constructing In2O3 thin films based FeFETs for energy-efficient nonvolatile ferroelectric field effect device applications. [ABSTRACT FROM AUTHOR]

We report the structural, dielectric, ferroelectric and magnetic properties of (1- x)BiFe 0.95 Ga 0.03 Mn 0.02 O 3 − x BaTiO 3 (BFGMO− x BTO) lead-free ceramics. Structural characterizations demonstrate that the BFGMO forms single-phase solid solutions with the BTO within the doping level of x = 0.3–0.65. With increasing the content of BTO the dielectric constant and ferroelectric Curie temperature shift towards lower temperatures, exhibiting relaxor-like ferroelectric behaviors. Moreover, the remnant polarization reaches the maximum value of 2 P r ~27.67 μC/cm2 at x = 0.35 near the morphotropic phase boundary. At room temperature, remnant magnetization increases - to the maximal value of 2 M r ~0.584 emu/g at x = 0.45, which is attributed to local lattice distortion and destruction of the spiral antiferromagnetic spin structure upon the doping of BTO. The coexistence of ferroelectric and ferromagnetic performance at room temperature makes the environment-friendly BFGMO− x BTO ceramics potential candidate for multiferroic device applications. [ABSTRACT FROM AUTHOR]

Here we report the structural, dielectric, ferroelectric, piezoelectric, and magnetic properties of zirconium-doped 0.67BiFeGaO-0.33BaZrTiO (BFG-BZT) lead-free ceramics. Structural investigations reveal that the doped Zr ions (up to x = 0.15) can be fully incorporated into the host lattice. Dielectric measurements demonstrate that with increasing Zr content, both the ferroelectric Curie temperature T and the dielectric constant decrease monotonously, and that the dielectric constant exhibits relaxor behaviors upon Zr doping. At the same time, the remnant polarization P increases and then decreases, with the maximum P ∼ 26 µC/cm for x = 0.025. One of the noteworthy results is that the remanent magnetic moment at room temperature increases up to 0.17 emu/g with increasing x from 0 to 0.15, which is attributed to enhanced lattice distortions due to Zr doping. The coexistence of strong ferroelectricity and ferromagnetism at room temperature implies that the BFG-BZT could be potential candidate materials for multiferroic device applications. [ABSTRACT FROM AUTHOR]

We synthesized In 3+ -doped Ba 0.85 Ca 0.15 TiO 3 :Er 3+ /Yb 3+ / x In 3+ lead-free ferroelectric ceramics that possess strong ferroelectricity and excellent upconversion luminescence under the excitation of 980 nm. With increasing x from 0, the green and red emission intensity increases and reaches the maximum at x =1.5% mol, then decreases slightly with further increase in x . For the x =1.5% sample the green emission intensity at 550 nm is ∼10 times larger than that of In 3+ undoped samples. Such a large In 3+ doping-induced enhancement of the luminescence is unprecedented for perovskite ferroelectrics. Based on the ultraviolet-visible-near infrared absorption spectra, the variation of the luminescence intensity with the In 3+ content was discussed. [ABSTRACT FROM AUTHOR]