This paper introduces a pioneering application of secondary ion mass spectrometry(SIMS)for estimating the electronic properties of Pb_(1-x)Sn_(x)Te,a compound categorized as a topological crystalline insulator.The pro...This paper introduces a pioneering application of secondary ion mass spectrometry(SIMS)for estimating the electronic properties of Pb_(1-x)Sn_(x)Te,a compound categorized as a topological crystalline insulator.The proposed approach marks the first application of SIMS for such estimations and focuses on investigating variations in ionization probabilities and shifts in the energy distribution of secondary ions.The ionization probabilities are influenced by pivotal parameters such as the material's work function and electron affinity.The derivation of these parameters hinges upon the energy gap's positioning relative to the vacuum level for varying values of within the Pb_(1-x)Sn_(x)Te compound.The findings elucidate noteworthy alterations in SIMS signals,particularly near the critical point of band-gap closing.展开更多
Pb_(x)Sr_(1-x)TiO_(3)(x=0.30,0.35,0.40,0.45,0.50 and 0.55)ceramics were fabricated by a solid-state reaction route.Xeray diffraction data at room temperature show PST samples shift from cubic to tetragonal phase with ...Pb_(x)Sr_(1-x)TiO_(3)(x=0.30,0.35,0.40,0.45,0.50 and 0.55)ceramics were fabricated by a solid-state reaction route.Xeray diffraction data at room temperature show PST samples shift from cubic to tetragonal phase with the increase of Pb^(2+) content.The microstructures were observed by scanning electron microscopy.Dielectric measurement was employed to investigate the ferroelectriceparaelectric phase transition behavior.Temperature dependent polarizationeelectric field hysteresis loops were conducted to study the electrocaloric effect(ECE)of the ferroelectric ceramics by indirect methods over a wide temperature range.Direct measurement of temperature change(DT)at room temperature for all samples can achieve 0.79e1.86 K.What's more,a giant ECE(△T=2.05 K,EC strength(△T/△E)=0.51×10^(-6) K m/V,under 40 kV/cm)was obtained in the sample of x=0.35 near phase transition temperature.Our results suggest that the ceramics are promising cooling materials with excellent EC properties for energy related applications.展开更多
文摘This paper introduces a pioneering application of secondary ion mass spectrometry(SIMS)for estimating the electronic properties of Pb_(1-x)Sn_(x)Te,a compound categorized as a topological crystalline insulator.The proposed approach marks the first application of SIMS for such estimations and focuses on investigating variations in ionization probabilities and shifts in the energy distribution of secondary ions.The ionization probabilities are influenced by pivotal parameters such as the material's work function and electron affinity.The derivation of these parameters hinges upon the energy gap's positioning relative to the vacuum level for varying values of within the Pb_(1-x)Sn_(x)Te compound.The findings elucidate noteworthy alterations in SIMS signals,particularly near the critical point of band-gap closing.
基金the National Natural Science Foundation of China(Grant Nos.11574057 and 51604087)the Guangdong Provincial Natural Science Foundation of China(Grant No.2016A030313718)the Science and Technology Program of Guangdong Province of China(Grant Nos.2016A010104018,and 2017A010104022).
文摘Pb_(x)Sr_(1-x)TiO_(3)(x=0.30,0.35,0.40,0.45,0.50 and 0.55)ceramics were fabricated by a solid-state reaction route.Xeray diffraction data at room temperature show PST samples shift from cubic to tetragonal phase with the increase of Pb^(2+) content.The microstructures were observed by scanning electron microscopy.Dielectric measurement was employed to investigate the ferroelectriceparaelectric phase transition behavior.Temperature dependent polarizationeelectric field hysteresis loops were conducted to study the electrocaloric effect(ECE)of the ferroelectric ceramics by indirect methods over a wide temperature range.Direct measurement of temperature change(DT)at room temperature for all samples can achieve 0.79e1.86 K.What's more,a giant ECE(△T=2.05 K,EC strength(△T/△E)=0.51×10^(-6) K m/V,under 40 kV/cm)was obtained in the sample of x=0.35 near phase transition temperature.Our results suggest that the ceramics are promising cooling materials with excellent EC properties for energy related applications.