124 research outputs found
Oxygen-vacancy-mediated Negative Differential Resistance in La and Mg co-substituted BiFeO3 Thin Film
The conductive characteristics of Bi0.9La0.1Fe0.96Mg0.04O3(BLFM) thin film
are investigated at various temperatures and a negative differential resistance
(NDR) is observed in the thin film, where a leakage current peak occurs upon
application of a downward electric field above 80 oC. The origin of the NDR
behavior is shown to be related to the ionic defect of oxygen vacancies (VO..)
present in the film. On the basis of analyzing the leakage mechanism and
surface potential behavior, the NDR behavior can be understood by considering
the competition between the polarized distribution and neutralization of VO..
Origin of the Enhanced Polarization in La and Mg Co-substituted BiFeO3 Thin Film during the Fatigue Process
We have studied the polarization fatigue of La and Mg co-substituted BiFeO3
thin film, where a polarization peak is observed during the fatigue process.
The origin of such anomalous behavior is analyzed on the basis of the defect
evolution using temperature-dependent impedance spectroscopy. It shows that the
motion of oxygen vacancies (VO..) is associated with a lower energy barrier,
accompanied by the injection of electrons into the film during the fatigue
process. A qualitative model is proposed to explain the fatigue behavior, which
involves the modification of the Schottky barrier upon the accumulation of VO..
at the metal-dielectric interface
6G Enabled Advanced Transportation Systems
The 6th generation (6G) wireless communication network is envisaged to be
able to change our lives drastically, including transportation. In this paper,
two ways of interactions between 6G communication networks and transportation
are introduced. With the new usage scenarios and capabilities 6G is going to
support, passengers on all sorts of transportation systems will be able to get
data more easily, even in the most remote areas on the planet. The quality of
communication will also be improved significantly, thanks to the advanced
capabilities of 6G. On top of providing seamless and ubiquitous connectivity to
all forms of transportation, 6G will also transform the transportation systems
to make them more intelligent, more efficient, and safer. Based on the latest
research and standardization progresses, technical analysis on how 6G can
empower advanced transportation systems are provided, as well as challenges and
insights for a possible road ahead.Comment: Submitted to an open access journa
Nonparaxiality-triggered Landau-Zener transition in topological photonic waveguides
Photonic lattices have been widely used for simulating quantum physics, owing
to the similar evolutions of paraxial waves and quantum particles. However,
nonparaxial wave propagations in photonic lattices break the paradigm of the
quantum-optical analogy. Here, we reveal that nonparaxiality exerts stretched
and compressed forces on the energy spectrum in the celebrated
Aubry-Andre-Harper model. By exploring the mini-gaps induced by the finite size
of the different effects of nonparaxiality, we experimentally present that the
expansion of one band gap supports the adiabatic transfer of boundary states
while Landau-Zener transition occurs at the narrowing of the other gap, whereas
identical transport behaviors are expected for the two gaps under paraxial
approximation. Our results not only serve as a foundation of future studies of
dynamic state transfer but also inspire applications leveraging nonparaxial
transitions as a new degree of freedom.Comment: 17 pages, 4 figure
Simulation of carbon peaking process of high energy consuming manufacturing industry in Shaanxi Province: A hybrid model based on LMDI and TentSSA-ENN
To achieve the goals of carbon peaking and carbon neutrality in Shaanxi, the high energy consuming manufacturing industry (HMI), as an important contributor, is a key link and important channel for energy conservation. In this paper, the logarithmic mean Divisia index (LMDI) method is applied to determine the driving factors of carbon emissions from the aspects of economy, energy and society, and the contribution of these factors was analyzed. Meanwhile, the improved sparrow search algorithm is used to optimize Elman neural network (ENN) to construct a new hybrid prediction model. Finally, three different development scenarios are designed using scenario analysis method to explore the potential of HMI in Shaanxi Province to achieve carbon peak in the future. The results show that: (1) The biggest promoting factor is industrial structure, and the biggest inhibiting factor is energy intensity among the drivers of carbon emissions, which are analyzed effectively in HMI using the LMDI method. (2) Compared with other neural network models, the proposed hybrid prediction model has higher accuracy and better stability in predicting industrial carbon emissions, it is more suitable for simulating the carbon peaking process of HMI. (3) Only in the coordinated development scenario, the HMI in Shaanxi is likely to achieve the carbon peak in 2030, and the carbon emission curve of the other two scenarios has not reached the peak. Then, according to the results of scenario analysis, specific and evaluable suggestions on carbon emission reduction for HMI in Shaanxi are put forward, such as optimizing energy and industrial structure and making full use of innovative resources of Shaanxi characteristic units
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