32 research outputs found
Emergence of ferromagnetism at the onset of moir\'e Kondo breakdown
The interaction of a lattice of localized magnetic moments with a sea of
conduction electrons in Kondo lattice models induces rich quantum phases of
matter, such as Fermi liquids with heavily renormalized electronic
quasiparticles, quantum critical non-Fermi liquid metals and unconventional
superconductors, among others. The recent demonstration of moir\'e Kondo
lattices has opened the door to investigate the Kondo problem with continuously
tunable parameters. Although a heavy Fermi liquid phase has been identified in
moir\'e Kondo lattices, the magnetic phases and Kondo breakdown transitions
remain unexplored. Here we report a density-tuned Kondo destruction in
AB-stacked MoTe2/WSe2 moir\'e bilayers by combining magneto transport and
optical studies. As the itinerant carrier density decreases, the Kondo
temperature decreases. At a critical density, we observe a heavy Fermi liquid
to insulator transition, and a nearly concomitant emergence of ferromagnetic
order. The observation is consistent with the scenario of a ferromagnetic
Anderson insulator and suppression of the Kondo screening effect. Our results
pave the path for inducing other exotic quantum phase transitions in moir\'e
Kondo lattices
Tuning the charge states in InAs/GaSb or InAs/GaInSb composite quantum wells by persistent photoconductivity
We have experimentally studied the persistent photoconductivity (PPC) in inverted InAs/GaSb and InAs/GaInSb quantum wells, which can be tuned into a bulk-insulating state by electron-hole hybridization. Specifically we tune the bulk band structure and carriers with light-emitting diode (LED) illuminations. The persistent photoconductivity could be negative or positive, depending on the specific doping structure and the illuminating photon energy. Compared to the widely-used electro-statically gating method, our findings provide a more flexible and non-invasive way to control the band structures and charge states in InAs/GaSb and InAs/GaInSb quantum wells (QWs)
Influence of hierarchical porosity on the mechanical properties of porous woven composites under thermomechanical loading
The manufacturing process often results in hierarchical microstructures of porous woven composites, with pores and cracks in the matrix and fibers ranging from nanometers to hundreds of micrometers. This research is devoted to the mechanical behavior of porous woven composites with hierarchical pores of very different sizes under thermomechanical loading. A micromechanics-based damage model is developed within the continuum damage mechanics (CDM) considering the contribution of hierarchical pores for capturing the thermomechanical behaviour of porous woven composites. The predicted results of the proposed model are compared with available experimental results as well as other analytical methods to verify its correctness. The main advantages of the proposed model, comparing to the existing counterparts, are that the contributions of hierarchical pores can be examined on the material macroscopic mechanical responses, and the capability in characterizing the damage behaviour of matrix and fibers. This work can provide theoretical guidance for controlling the formation of hierarchical porosity during the manufacturing process. (C) 2020 Elsevier Ltd. All rights reserved
Tuning the charge states in InAs/GaSb or InAs/GaInSb composite quantum wells by persistent photoconductivity
We have experimentally studied the persistent photoconductivity (PPC) in inverted InAs/GaSb and InAs/GaInSb quantum wells, which can be tuned into a bulk-insulating state by electron-hole hybridization. Specifically we tune the bulk band structure and carriers with light-emitting diode (LED) illuminations. The persistent photoconductivity could be negative or positive, depending on the specific doping structure and the illuminating photon energy. Compared to the widely-used electro-statically gating method, our findings provide a more flexible and non-invasive way to control the band structures and charge states in InAs/GaSb and InAs/GaInSb quantum wells (QWs)
Research on the Influence of Battery Cell Static Parameters on the Capacity of Different Topology Battery Packs
The parameter inconsistency of the battery cells and the series-parallel connection mode are closely related to the battery pack capacity. Studying the degree of influence of battery pack capacity by battery cell parameters is of great significance to the series-parallel design of battery packs. This paper establishes battery cell models and battery pack models with different topologies. In the MATLAB/Simulink environment, simulation studies were conducted to study the influence of the battery pack capacity by the monomer parameters as the number of cells in series and parallel in the topology changes. Then, from a statistical point of view, the simulation results were analyzed in principle. Finally, a small-scale battery pack experimental platform was built in the laboratory environment to verify the correctness of the simulation conclusions and theoretical analysis
Frequency-Induced Inflection Point Phenomenon and Formation Mechanism of Partial Discharge With Polyimide Films
Non-Gaussian approximation iterative receiver for MIMO-OFDM vehicular networks
Multiple-Input Multiple-Output - Orthogonal Frequency Division Multiplexing (MIMO-OFDM) is adopted to vehicular networks to increase the capacity, reliability and speed. In this paper, iterative demodulation and decoding algorithms are studied to approach the capacity of MIMO-OFDM vehicular networks. By analysing the drawbacks of the Gaussian approximation on the interference cancellation, Non-Gaussian approximation is proposed to enhance the performance of interference cancellation based detectors with large constellations. Simulation results demonstrate that the proposed non-Gaussian algorithm can achieve a significant performance gain over existing ones with high order constellations.EICPCI-S(ISTP)[email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]
Data from: Effect of H. pylori infection on cytokine profiles and oxidative balance in subjects with chronic alcohol ingestion
Different amounts of ingested alcohol can have distinct effects on the human body. However, there is limited research on chronic alcohol consumption with Helicobacter pylori infection. We sought to investigate the relationship between the cytokine profile, oxidative balance and H. pylori infection in subjects with chronic alcohol consumption. A total of 142 subjects were divided into three groups: 59 subjects with chronic alcohol ingestion and H. pylori infection (group A); 53 subjects with chronic alcohol ingestion without H. pylori infection (group B); and 30 control subjects (group C). The serum levels of CagA, interleukin (IL)-10, E-selectin, TNF-α, malondialdehyde (MDA) and superoxide dismutase (SOD) activity were measured by enzyme-linked immunosorbent assay (ELISA). We found that the ages and serum H. pylori CagA levels among the three groups, as well as both the mean drinking age and the mean daily alcohol consumption between groups A and B, were matched and comparable. Comparing the BMIs among the three groups, the BMI differences were found to be statistically significant (F=3.921, P0.05). Additionally, no differences in the serum CagA levels were found in comparisons among the groups (all P>0.05). The serum IL-10 and E-selectin levels in group A were significantly lower than those in group B (serum IL-10: P0.05). Furthermore, the serum IL-10 and E-selectin levels in group B were significantly higher than those in group C (serum IL-10: P0.05). Although the serum levels of MDA and SOD in groups A and B were slightly lower than those in group C, there were no significant differences among groups (all P>0.05). In conclusion, we believe that H. pylori infection might cause a significant inhibition of certain cytokine profiles in subjects with chronic alcohol ingestion. Moreover, chronically ingested alcohol may exert an adjusted inflammatory effect, but there was no association between H. pylori infection, chronic alcohol consumption and oxidative balance