共查询到20条相似文献,搜索用时 15 毫秒
1.
采用化学镀方法成功制备了自带电容构成LC共振回路的CoP/Insulator/BeCu复合结构丝. 研究了这种新型复合结构丝产生LC共振型巨磁阻抗效应的特征,长度为lm=95 cm的复合结构丝,当驱动电流频率为LC共振频率fr=290 MHz时,LC共振型巨磁阻抗效应为4875%,磁场灵敏度为046%/A·m-1,大于常规复合结构丝;远离此频率时的巨
关键词:
复合结构丝
LC共振')" href="#">LC共振
等效电路模型
巨磁阻抗效应 相似文献
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用射频溅射法制备了Fe71.5Cu1Cr2.5V4Si12B9单层膜和结构为(F/S)3/M/(F/S)3的多层膜,在制备过程中加72kA/m的纵向磁场.研究表明在制备过程中加磁场明显改善了材料的软磁性能,降低了材料的矫顽力.将样品经不同温度退火热处理后,发现经230℃退火1.5h的单层膜和多层膜具有最佳的软磁性能和最大的磁阻抗效应,单层膜最大横向磁阻抗比为37.5%,多层膜最大横向磁阻抗比高达277%.通过比较单层和多层膜磁阻抗效应随频率和磁场的变化,发现多层膜具有较低的磁阻抗效应的临界频率和峰值特征频率,和较大的磁阻抗变化率,而且有较低的横向磁阻抗效应的饱和场.
关键词:
铁基合金
多层膜
巨磁阻抗效应 相似文献
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The highly sensitive giant magneto-impedance effect in a solenoid containing a magnetic core of Fe36Co36Nb4Si4.8B19.2 (FeCo-based) ribbon under a weak magnetic field (WMF) is presented in this paper. The FeCo-based amorphous ribbon is prepared by single roller quenching and annealed with Joule heat in a flowing nitrogen atmosphere. The giant magnetoimpedance effect in solenoid (GMIES) profiles are measured with an HP4294A impedance analyzer. The result shows that the GMIES responds to the WMF sensitively (as high as 1580 %/A穖-1). The high sensitivity can be obtained in a moderate narrow range of annealing current density (30-34 A/mm2) and closely depends on the driven current frequency. The highest sensitivity (1580 %/A穖-1) is obtained when the FeCo-based amorphous ribbon is annealed at 32 A/mm2 for 10 min and then driven with an alterning current (AC) at the frequency of 350 kHz. The highly sensitive GMIES under the WMF may result from the multiple magnetic-anisotropic structure, which is induced by the temperature gradient produced during Joule-heating the ribbon. 相似文献
6.
The highly sensitive giant magneto-impedance effect in a solenoid containing a magnetic core of Fe36Co36Nb4Si4.8B19.2(FeCo-based) ribbon under a weak magnetic field(WMF) is presented in this paper.The FeCo-based amorphous ribbon is prepared by single roller quenching and annealed with Joule heat in a flowing nitrogen atmosphere.The giant magnetoimpedance effect in solenoid(GMIES) profiles are measured with an HP4294A impedance analyzer.The result shows that the GMIES responds to the WMF sensitively(as high as 1580 %/A·m 1).The high sensitivity can be obtained in a moderate narrow range of annealing current density(30-34 A/mm 2) and closely depends on the driven current frequency.The highest sensitivity(1580 %/A·m 1) is obtained when the FeCobased amorphous ribbon is annealed at 32 A/mm 2 for 10 min and then driven with an alterning current(AC) at the frequency of 350 kHz.The highly sensitive GMIES under the WMF may result from the multiple magnetic-anisotropic structure,which is induced by the temperature gradient produced during Joule-heating the ribbon. 相似文献
7.
Giant resonance enhancement is demonstrated to be due to the Fano interference in a grating waveguide composed of gain-assisted silicon slabs. The Fano mode is characterized by its ultra-narrow asymmetric spectrum, different from that of a pure electric or magnetic dipole. The simulation indicates that a sharp Fano-interfered lineshape is responsible for the giant resonance enhancement featuring the small-gain requirements. 相似文献
8.
根据用原子力显微镜对Fe基纳米晶Fe73.5Cu1Nb3Si13.5B9合金薄带的介观结构和巨磁阻抗效应的实验研究结果,提出了纳米晶软磁合金巨磁阻抗效应受其介观结构影响的理论模型.该模型成功地解释了低频对纳米晶软磁合金巨磁阻抗效应的影响,反映了现有“三明治”理论的主要特征,并弥补了它的不足;同时指出了纳米晶粒电导率σ、磁导率μ对合金巨磁阻抗效应有影响.
关键词:
铁基纳米晶合金
介观结构
巨磁阻抗效应
介观模型 相似文献
9.
对Co基熔体抽拉非晶丝进行了普通炉内退火和不同磁场强度(500 Oe,1600 Oe,4000 Oe)下的横向和纵向磁场退火,利用HP4192阻抗分析仪和Lakeshore7407VSM分析了退火态样品的巨磁阻抗(GMI)效应和软磁性能.研究结果表明,纵向磁场降低了环向各向异性,纵向磁场退火样品GMI效应降低且GMI曲线为单峰,最大阻抗变化率ΔZ/Z为131%,磁场响应灵敏度为7%/Oe;而横向磁场提高了环向畴体积,增加了环向各向异性场,导致退火样品GMI曲线随频率升高由单峰转
关键词:
非晶丝
巨磁阻抗效应
退火 相似文献
10.
The Helmholtz SchrSdinger method is employed to study the electric field standing wave caused by coupling through a simple slot. There is a good agreement between the numerical results and the resonant conditions presented by the Helmholtz-Schrodinger method. Thus, it can be used in similar cases where the amplitude of the electric field is the important quantity or eigenfunctions of the Schrodinger equation are needed for complicated quantum structures with hard wall boundary conditions. 相似文献
11.
Yi Zhang Senfu ZhangCaiqin Luo Juan DongQingfang Liu Jianbo Wang 《Journal of magnetism and magnetic materials》2012
An easy method of tuning the response of maximum magnetoimpedance (MI) ratio in Fe75.5Si13.5B7Nb3Cu1 amorphous ribbons was investigated by laser ablation. In order to obtain different GMI peak positions, the stripes were ablated by laser with different separations on the surface layer of the ribbon. When the stripes were parallel (or perpendicular) to the applied magnetic field, the peak location of maximum MI ratio would drift to larger (or smaller) external field. And the shift was correlated with the spaces between stripes. The applied fields corresponding to the minimum and maximum values of peak location are 13 Oe and 49 Oe at the frequency of 15 MHz, respectively. The phenomenon can be explained by the anisotropy field induced by demagnetizing field after the laser ablation. 相似文献
12.
M. I. Dykman D. G. Luchinsky R. Mannella P. V. E. McClintock N. D. Stein N. G. Stocks 《Journal of statistical physics》1993,70(1-2):463-478
The response of a bistable noise-driven system to a weak periodic force is investigated using linear response theory (LRT) and by analogue electronic experiment. For quasithermal systems the response, and in particular its increase with increasing noise intensityD, are described by the fluctuationdissipation relations. For smallD the low-frequency susceptibility of the system() has been found in explicit form allowing for both forced oscillations about the states and periodic modulation of the probabilities of fluctuational transitions between the states. It is shown, both theoretically and experimentally, that a phase lag between the force and the response passes through a maximum whenD is tuned through the range where stochastic resonance (SR) occurs. A giant nonlinearity of the response is shown to arise for smallD and small frequencies of the driving force. It results in the signal induced by a sinusoidal force being nearly rectangular. The range of applicability of LRT is established. 相似文献
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We use a simple model of Bullard-type disc dynamo, in which the disc rotation rate is subject to harmonic oscillations, to analyze the generation of magnetic field by the parametric resonance mechanism. The problem is governed by a damped Mathieu equation. The Floquet exponents, which define the magnetic field growth rates, are calculated depending on the amplitude and frequency of the oscillations. Firstly, we show that the dynamo can be excited at significantly subcritical disc rotation rate when the latter is subject to harmonic oscillations with a certain frequency. Secondly, at supercritical mean rotation rates, the dynamo can also be suppressed but only in narrow frequency bands and at sufficiently large oscillation amplitudes. 相似文献
14.
研究了Fe36Co36Nb4Si4.8B19.2合金薄带为磁芯的螺线管(FeCo基磁芯螺线管)的巨磁阻抗效应与磁芯长度之间的关系.研究结果表明,磁芯长度是影响FeCo基磁芯螺线管巨磁阻抗效应的重要因素.当磁芯长度小于螺线管长度时,磁芯螺线管巨磁阻抗的最大值(ΔZ/Z)max与磁芯长度呈线性关系,其线性相关系数可以根据电磁学理论推导得到;当磁芯的长度大于螺线管的长度时,由于漏磁作用,(ΔZ/Z)max与磁芯长度的关系偏离了线性关系,(ΔZ/Z)max与磁芯长度的关系曲线中有一个极值点,(ΔZ/Z)max在极值点达到最大.磁芯螺线管巨磁阻抗效应曲线的尖刺部分高度(ΔZ/Z)T与磁芯长度的关系也有类似的极值点,(ΔZ/Z)T在极值点达到最大值.磁芯螺线管巨磁阻抗效应曲线的尖刺部分对弱磁场敏感,受磁芯退磁场的影响明显,磁芯的退磁场与磁芯长度呈负指数关系.
关键词:
磁芯螺线管
FeCo基合金薄带
巨磁阻抗效应
磁芯长度 相似文献
15.
Time-varying coupling-induced logical stochastic resonance in a periodically driven coupled bistable system 下载免费PDF全文
《中国物理 B》2021,30(6):60503-060503
Coupling-induced logical stochastic resonance(LSR) can be observed in a noise-driven coupled bistable system where the behaviors of system can be interpreted consistently as a specific logic gate in an appropriate noise level. Here constant coupling is extended to time-varying coupling, and then we investigate the effect of time-varying coupling on LSR in a periodically driven coupled bistable system. When coupling intensity oscillates periodically with the same frequency with periodic force or relatively high frequency, the system successfully yields the desired logic output. When coupling intensity oscillates irregularly with phase disturbance, large phase disturbance reduces the area of optimal parameter region of coupling intensity and response speed of logic devices. Although the system behaves as a desired logic gate when the frequency of time-periodic coupling intensity is precisely equal to that of periodic force, the desired logic gate is not robust against tiny frequency difference and phase disturbance. Therefore, periodic coupling intensity with high frequency ratio is an optimal option to obtain a reliable and robust logic operation. 相似文献
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We studied the motion of an underdamped Brownian particle in a periodic potential subject to a harmonic excitation and a colored noise. The average input energy per period and the phase lag are calculated to quantify the phenomenon of stochastic resonance (SR). The numerical results show that most of the out-of-phase trajectories make a transition to the in-phase state as the temperature increases. And the colored noise delays the transitions between these two dynamical states. The each curve of the average input energy per period and the phase lag versus the temperature exist a mono peak and SR appears in this system. Moreover, the optimal temperature where the SR occurs becomes larger and the region of SR grows wider as the correlation time of colored noise increases. 相似文献
18.
We investigate stochastic resonance (SR) in the
FitzHugh--Nagumo system under combined bounded noise and weak
harmonic excitation. Taking a spectral amplification factor as a
signal-to-noise ratio, we show numerically that bounded noise can
induce SR by adjusting either the intensity of bounded noise or its
colour. Moreover, the increase of noise colour can enhance the SR
and make the peak of the SR shift toward lower noise intensities, which
is more feasible in practice. Since bounded noise is flexible to
model random excitation, these findings may have some potential
applications in engineering, neuroscience and biology. 相似文献
19.
F. Béron L.A. ValenzuelaM. Knobel L.G.C. MeloK.R. Pirota 《Journal of magnetism and magnetic materials》2012,324(8):1601-1605
We applied the first-order reversal curve method to hysteretic giant magnetoimpedance (GMI) of soft magnetic amorphous ribbons with a well-defined transversal domain structure and quasi-anhysteretic magnetization behavior. In opposition to major curve, it gives access to the distribution of local irreversible changes of the transverse permeability, which undergo a gradual transition. Results show that hysteretic GMI effect consists of three distinct regimes depending on the applied field. An interlinked hysteron/anti-hysteron model is proposed to analyze the obtained results, which allows one to follow the influence of frequency and anisotropy upon the irreversible switches probed by GMI. 相似文献
20.
The Helmholtz-Schrdinger method is employed to study the electric field standing wave caused by coupling through a simple slot. There is a good agreement between the numerical results and the resonant conditions presented by the Helmholtz-Schrdinger method. Thus, it can be used in similar cases where the amplitude of the electric field is the important quantity or eigenfunctions of the Schrdinger equation are needed for complicated quantum structures with hard wall boundary conditions. 相似文献