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基于室温铁磁性的(Fe,Al)共掺杂SiGe铁磁pn二极管的可调整流和磁阻特性

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Science China Materials 2024年第2期67卷 573-579页

作者：李加飞张析向钢 College of Physics Sichuan UniversityChengdu 610064China

Ⅳ族稀磁半导体因其优异的磁电性能,以及在与当前主流半导体集成技术兼容的自旋电子器件中具有广阔的应用前景而受到越来越多的关注.事实上,具有室温铁磁性的Ⅳ族稀磁半导体及其衍生器件更有望在实际中得以应用.本工作设计并制备了基于p... 详细信息

Ⅳ族稀磁半导体因其优异的磁电性能,以及在与当前主流半导体集成技术兼容的自旋电子器件中具有广阔的应用前景而受到越来越多的关注.事实上,具有室温铁磁性的Ⅳ族稀磁半导体及其衍生器件更有望在实际中得以应用.本工作设计并制备了基于p型(Fe,Al)共掺杂SiGe薄膜和n型Ge衬底的磁性pn二极管.磁性测量以及磁阻和反常霍尔效应测试揭示了p型(Fe,Al)共掺杂SiGe薄膜的室温铁磁性.有趣的是,磁性pn异质结表现出磁场可调的整流和磁阻行为.我们的研究结果为制备具有室温铁磁性的Ⅳ族稀磁半导体提供了一种可选策略,并为Ⅳ族稀磁半导体的实际自旋电子应用提供了范例.

关键词： diluted magnetic semiconductor SiGe pn junction rectification magnetoresistance

A valveless piezoelectric pump with novel flow path design of function of rectification to improve energy efficiency

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Frontiers of Mechanical Engineering 2022年第3期17卷 177-193页

作者： Jianhui ZHANG Xiaosheng CHEN Zhenlin CHEN Jietao DAI Fan ZHANG Mingdong MA Yuxuan HUO Zhenzhen GUI School of Mechanical and Electrical Engineering Guangzhou UniversityGuangzhou510006China

Existing valveless piezoelectric pumps are mostly based on the flow resistance mechanism to generate unidirectional fluid pumping,resulting in inefficient energy conversion because the majority of mechanical energy is consumed in terms of parasitic loss.In this paper,a novel tube structure composed of a Y-shaped tube and aȹ-shaped tube was proposed considering theory of jet inertia and vortex dissipation for the first time to improve energy efficiency.After verifying its feasibility through the flow field simulation,the proposed tubes were integrated into a piezo-driven chamber,and a novel valveless piezoelectric pump with the function of rectification(NVPPFR)was reported.Unlike previous pumps,the reported pump directed the reflux fluid to another flow channel different from the pumping fluid,thus improving pumping efficiency.Then,mathematical modeling was established,including the kinetic analysis of vibrator,flow loss analysis of fluid,and pumping efficiency.Eventually,experiments were designed,and results showed that NVPPFR had the function of rectification and net pumping effect.The maximum flow rate reached 6.89 mL/min,and the pumping efficiency was up to 27%.The development of NVPPFR compensated for the inefficiency of traditional valveless piezoelectric pumps,broadening the application prospect in biomedicine and biology fields.

关键词： composite tube valveless piezoelectric pump rectification energy efficiency

rectification and electroluminescence of nanostructured GaN/Si heterojunction based on silicon nanoporous pillar array

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Chinese Physics B 2015年第10期24卷 432-437页

作者：王小波李勇闫玲玲李新建 Department of Physics and Laboratory of Material Physics Zhengzhou University College of Physics and Electrical Engineering Anyang Normal University Department of Physics Pingdingshan University

A GaN/Si nanoheterojunction is prepared through growing Ga N nanocrystallites（nc-GaN） on a silicon nanoporous pillar array（Si-NPA） by a chemical vapor deposition（CVD） technique at a relatively low temperature. The average size of nc-Ga N is determined to be ~10 nm. The spectral measurements disclose that the photoluminescence（PL） from GaN/SiNPA is composed of an ultraviolet（UV） band and a broad band spanned from UV to red region, with the feature that the latter band is similar to that of electroluminescence（EL）. The electron transition from the energy levels of conduction band and, or, shallow donors to that of deep acceptors of Ga N is indicated to be responsible for both the broad-band PL and the EL luminescence. A study of the I-V characteristic shows that at a low forward bias, the current across the heterojunction is contact-limited while at a high forward bias it is bulk-limited, which follows the thermionic emission model and space-charge-limited current（SCLC） model, respectively. The bandgap offset analysis indicates that the carrier transport is dominated by electron injection from n-GaN into the p-Si-NPA, and the EL starts to appear only when holes begin to be injected from Si-NPA into GaN with biases higher than a threshold voltage.

关键词： GaN/Si-NPA heterojunction rectification electroluminescence （EL）

rectification effect in asymmetric Kerr nonlinear medium

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Chinese Physics B 2014年第6期23卷 278-282页

作者：刘晚果潘风明蔡力伟 Department of Applied Physics Nanjing University of Aeronautics and Astronautics

Based on the transfer matrix method, the recursion of an electromagnetic wave propagating in an asymmetric Kerr nonlinear medium is analytically formulated, from which the rectification effect is clearly presented. The effects on the rectification regioh of the linear part and nonlinear coefficient of permittivity are both studied, and the energy densities before and after rectification are discussed. We use a rectifying factor to describe the intensity of the rectification effect. The result shows that every transmission peak is divided into two parts when the symmetry is broken, and nonlinear asymmetry has a more significant effect on the rectification effect than the linear asymmetry. The rectification intensity and area will be enlarged when the asymmetry factor is increased in a certain range.

关键词： rectification transfer matrix method Kerr nonlinearity asymmetry

Spin-excited states and rectification in an organic spin rectifier

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Chinese Physics B 2014年第8期23卷 495-501页

作者：左梦莹胡贵超李营任俊峰王传奎 College of Physics and Electronics Shandong Normal University

Spin-excited states in an asymmetric magnetic organic co-oligomer diode are investigated theoretically. The results demonstrate that the structural asymmetry of the co-oligomer is modulated by the spin-excited states, which is embodied in the wave functions of the eigenstates as well as the spin density wave. By calculating the transport property, a robust spin-current rectification concomitant with a charge-current rectification is observed in all spin-excited states. However, the current through the diode is suppressed distinctly by the spin-excited states, while the rectification ratios may be reduced or enhanced depending on the bias and the excited spins. The intrinsic mechanism is analyzed from the spin-dependent trans- mission combined with the change of molecular eigenstates under bias. Finally, the temperature-induced spin excitation is simulated. Significant rectification behavior is obtained even at room temperature.

关键词： organic spintronics organic ferromagnet rectification spin-excited state

Length dependence of rectification in organic co-oligomer spin rectifiers

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Chinese Physics B 2016年第5期25卷 333-338页

作者：胡贵超张朝李营任俊峰王传奎 School of Physics and Electronics Shandong Normal University

The rectification ratio of organic magnetic co-oligomer diodes is investigated theoretically by changing the molecular length. The results reveal two distinct length dependences of the rectification ratio： for a short molecular diode, the chargecurrent rectification changes little with the increase of molecular length, while the spin-current rectification is weakened sharply by the length; for a long molecular diode, both the charge-current and spin-current rectification ratios increase quickly with the length. The two kinds of dependence switch at a specific length accompanied with an inversion of the rectifying direction. The molecular ortibals and spin-resolved transmission analysis indicate that the dominant mechanism of rectification suffers a change at this specific length, that is, from asymmetric shift of molecular eigenlevels to asymmetric spatial localization of wave functions upon the reversal of bias. This work demonstrates a feasible way to control the rectification in organic co-oligomer spin diodes by adjusting the molecular length.

关键词： organic spintronics organic ferromagnet rectification

Mechanisms Causing Ballistic Thermal rectification

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Chinese Physics Letters 2014年第4期31卷 118-121页

作者： DING Xing MING Yi School of Physics and Material Science Anhui University Hefei 230601

The mechanism causing the ballistic thermal rectification in the harmonic system is analytically studied. Using the conceptual model of a dephasing probe, we obtain that phase breaking is unnecessary to realize the ballistic thermal rectification. However, it can change the strength of rectification. Asymmetric phonon-phonon interac- tion inducing the energy exchange of the normal mode of vibration is necessary to realize the ballistic thermal rectification. Moreover, the quantum statistics of phonons in at least one thermal reservoir is crucial to guarantee the asymmetric phonon-phonon interaction.

关键词： rectification Mechanisms ballistic

Ion current rectification: from nanoscale to microscale

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Science China Chemistry 2019年第10期62卷 1346-1359页

作者： Tianyi Xiong Kailin Zhang Yanan Jiang Ping Yu Lanqun Mao Beijing National Laboratory for Molecular Sciences Key Laboratory of Analytical Chemistry for Living BiosystemsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100149China

Ion current rectification(ICR)is an electrodynamic phenomenon in electrolyte solution which is defined as the asymmetric potential-dependent ion flux through a confined environment,giving rise to asymmetric electrical current-voltage characteristics induced by the influence of an asymmetric electrical double layer structure.Since the discovery of the ICR phenomenon,the observation and application of ICR at nanoscale and microscale have been widely investigated experimentally and theoretically.Here,the recent progress of ICR from nanoscale to microscale is systematically reviewed.Nano/micropore structures of different materials,shapes and pore sizes are first discussed.Then,the factors influencing ICRs by thermodynamically or kinetically regulating the electrical double layer structure are introduced.Moreover,theoretical models are presented to explain the mechanism of ICRs.Based on the understanding of this phenomenon,the applications,especially in biosensors,are discussed.Finally,future developments of this area are briefly presented.This review covers the representative related literature published since 2010 and is intended to give a systematic introduction to this area.

关键词： ion current rectification ion transport nanopore nanochannel micropipette

The effects of contact configurations on the rectification of dipyrimidinyl-diphenyl diblock molecular junctions

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Chinese Physics B 2011年第12期20卷 389-394页

作者：张广平胡贵超李宗良王传奎 College of Physics and Electronics Shandong Normal University

The transport properties of a conjugated dipyrimidinyl-diphenyl diblock oligomer sandwiched between two gold electrodes, as recently reported by [Diez-Perez et al. Nature Chem. 1 635 （2009）], are theoretically investigated using the fully self-consistent nonequilibrium Green＇s function method combined with density functional theory. Two kinds of symmetrical anchoring geometries are considered. Calculated current-voltage curves show that the contact structure has a strong effect on the rectification behaviour of the molecular diode. For the equilateral triangle configuration, pronounced rectification behaviour comparable to the experimental measurement is revealed, and the theoretical analysis indicates that the observed rectification characteristic results from the asymmetric shift of the perturbed molecular energy levels under bias voltage. While for the tetrahedron configuration, both rectification and negative differential conductivity behaviours are observed. The calculated results further prove the close dependence of the transporting characteristics of molecular junctions on contact configuration.

关键词： molecular electronic device rectification electronic transport property