Dissertation > Excellent graduate degree dissertation topics show

Theoretical Analysis of Giant Magneto Impedance Effect in Sandwiched Film

Author: WangXia
Tutor: ZhengZuo；WangAiLing；JiangHongWei
School: Capital Normal University
Course: Optics
Keywords: GMI Sandwich membrane Effective permeability
CLC: O484.4
Type: Master's thesis
Year: 2005
Downloads: 116
Quote: 0
Read: Download Dissertation

Abstract


Magnetic impedance effect of the applied dc magnetic field , showing rapid response, high sensitivity variation of the phenomenon is known as the GMI (Giant Magneto Impedance effect, GMI effect). Recent studies indicate that a soft magnetic alloy covered with a layer of highly conductive metal layer multilayer film has significant GMI effect . This thesis is based on GMI has actual sandwich sample conditions, make a sandwich structure as the theoretical model : Sandwiches model ferromagnetic outer layers of the middle conductive layer and the conductive layer is smaller than the width of the ferromagnetic layer width , so that the upper and lower ferromagnetic layer form a closed structure . Using the static and dynamic magnetization magnetization method separately , taking into account the magnetic domain wall movement and rotation of two kinds of magnetic domains of mechanisms , for multilayer films derived longitudinal GMI theoretical study permeability tensor full expression . According to the effective permeability tensor expressions , the use of certain boundary conditions magnetic vector Maxwell equations and Landau-Lifshitz equation model for closed sandwich theoretical calculations, the impedance versus frequency , anisotropy field , film thickness and conductivity as a function of other factors . The results show that : the magnetic anisotropy value H_k equivalent field is smaller, the smaller the angle with the easy axis direction GMI effect is more obvious. Based on this , the magnetic anisotropy field of size equivalent 3Oe, the direction along the easy axis direction multilayer film further theoretical calculation results can be summarized as follows: ( 1 ) a high frequency impedance of the DC magnetic field applied ( equivalent to approximately equal to the anisotropy field ) for a maximum value ; ( 2 ) multilayer sandwich the frequency is 1MHz GMI effect near the maximum value ; ( 3 ) the greater the conductivity of the conductive layer multilayer film GMI effect appears stronger ; ( 4 ) the total thickness of the film requires a certain layer , a ferromagnetic layer and a conductive layer there is an optimal film thickness. ( 5 ) is equivalent to the magnetic anisotropy field is smaller, and the angle between the direction of the external magnetic field direction and the larger , GMI ratios greater .

Related Dissertations

  1. Research on Magnetic Field Sensor Based on GMI Effect and Geomagnetic Matching Algorithm,P318
  2. Giant Magneto-Impedance of NiFe/Cu and NiFeMo/Cu Composite Wire Produced by Pulsed Electrodeposition,TG132.27
  3. Sandwich structure thin film GMI effect of electromagnetic theory,O484.43
  4. Theoretical Study on Influence of Mesoscopic Structure of Fe73.5Cu1Nb3Si13.5B9 Nanocrystalline Alloy on Its Magnetic Performance,TB383.1
  5. Non-linear Damage Mechanics Theory of Coupled Fluid-Solid with Numerical Analysis of Geo-Materials,TU452
  6. Preparation of TiO_2 anodized nanotubes Its Application in Dye -sensitized solar cells and photocatalytic application,TB383.1
  7. CoP / Insulator / BeCu composite wire preparation and giant magneto-impedance effect of,TG174.4
  8. Different annealing on Co-based amorphous glass-enclosed wire GMI Effect,O469
  9. Electroless CoNiP / Cu composite wire GMI effect of,O482.5
  10. GMI new method for preparing thin films and detection system design,O484
  11. Magnetic particles electromagnetic properties of composite media,O482.5
  12. Research of Giant Magnetoimpedance Effect Based in Current Sensor,TP212.1
  13. Giant Magneto-Impedance Effect of Magnetron Sputtered Composite Wires,O482.5
  14. Amorphous and nanocrystalline soft magnetic properties of glass wrapped wire and giant magneto- impedance effect in,O482.5
  15. Miniature magnetic sensor technology based on amorphous GMI effect,TP212
  16. Giant Magnetoimpedance Effect of Electroless-deposited NiFeP/BeCu Composite Wire,TB39
  17. Fractal branching tree structure characteristics of conduction,O415
  18. Electromagnetic wave absorbing composite equivalent parameters of microwave,TM25
  19. Cobalt-based soft magnetic properties of glass wrapped wire Optimization,O482.5
  20. Co-based amorphous wire complex magnetic field modulation processing and electroplating Ni connecting basic research,TM271

CLC: > Mathematical sciences and chemical > Physics > Solid State Physics > Thin Film Physics > The nature of the films
© 2012 www.DissertationTopic.Net  Mobile