• Title/Summary/Keyword: bias field

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Effect of Bias Magnetic Field on Magnetoelectric Characteristics in Magnetostrictive/Piezoelectric Laminate Composites

  • Chen, Lei;Luo, Yulin
    • Journal of Magnetics
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    • v.20 no.4
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    • pp.347-352
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    • 2015
  • The magnetoelectric (ME) characteristics for Terfenol-D/PZT laminate composite dependence on bias magnetic field is investigated. At low frequency, ME response is determined by the piezomagnetic coefficient $d_{33,m}$ and the elastic compliance $s_{33}^H$ of magnetostrictive material, $d_{33,m}$ and $s_{33}^H$ for Terfenol-D are inherently nonlinear and dependent on $H_{dc}$, leading to the influence of $H_{dc}$ on low-frequency ME voltage coefficient. At resonance, the mechanical quality factor $Q_m$ dependences on $H_{dc}$ results in the differences between the low-frequency and resonant ME voltage coefficient with $H_{dc}$. In terms of ${\Delta}E$ effect, the resonant frequency shift is derived with respect to the bias magnetic field. Considering the nonlinear effect of magnetostrictive material and $Q_m$ dependence on $H_{dc}$c, it predicts the low-frequency and resonant ME voltage coefficients as a function of the dc bias magnetic field. A good agreement between the theoretical results and experimental data is obtained and it is found that ME characteristics dependence on $H_{dc}$ are mainly influenced by the nonlinear effect of magnetostrictive material.

A Study on $E_1$Transition in Si-Doped $Al_{0.32}Ga_{0.68}As$by Electroreflectance Measurement (Electroreflectance 측정에 의한 Si이 첨가된 $Al_{0.32}Ga_{0.68}As$에서의 $E_1$ 전이에 대한 연구)

  • 김동렬;손정식;김근형;이철욱;배인호
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.11 no.9
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    • pp.687-692
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    • 1998
  • Silicon doped $Al_{0.32}Ga_{0.68}As$ were growth by molecular beam epitaxy. Electroreflectance(ER) spectra of the $E_1$ transition of Schottky barrier Au/n-$Al_{0.32}Ga_{0.68}As$ have been measured at various modulation voltage($V_{ac}$) and dc bias voltage($V_{bias}$). from the $E_1$peak, band gap energy of the $Al_{0.32}Ga_{0.68}As$ is 1.883 eV which corresponds to an Al composition of 32%. As modulation voltage($V_{bias}$) is changed, a line shape at the $E_1$transition does not change, but its amplitude varies linearly. The amplitude of $E_1$signal decrease with increasing the forward dc bias voltage($V_{bias}$), but the line shape does not change. It suggests that the low field theory rather than Franz-Keldysh oscillation is Required to interpret spectra. Also, spectra at the $E_1$transition were broadened with increasing the reverse dc bias voltage($V_{bias}$) which suggests the presence of Field-induced broadening.

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Effects of Annealing on Electrical Characteristics of Double-Gated Silicon Nanosheet Feedback Field-Effect Transistors (더블게이트 실리콘 나노시트 피드백 전계효과 트랜지스터의 전기적 특성에 미치는 열처리 효과)

  • Hyojoo Heo;Yunwoo Shin;Jaemin Son;Seungho Ryu;Kyoungah Cho;Sangsig Kim
    • Journal of IKEEE
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    • v.27 no.4
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    • pp.418-424
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    • 2023
  • In this study, we examined the effects of annealing on electrical characteristics of double-gated silicon nanosheet (SiNS) feedback field effect transistors (FBFETs). When bias stresses were applied for 1000 s, the double-gated SiNS FBFETs were more affected by positive bias stresses than negative bias stresses regardless of the channel mode owing to the increase of interface traps caused by electrons in the inversion layers. After annealing at 300 ℃ for 10 mins, the devices were completely recovered to their original properties, and the characteristics did not change anymore when bias stresses were applied again for 1000 s.

The Formation of Reserved Field Configuration with Bias Field and Radio-Frequency Rotating Field (바이어스 자계와 고주파 회전자계에 의한 역전자계 배위 형성)

  • 채규훈;김동필
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.38 no.10
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    • pp.840-847
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    • 1989
  • It is an important problem that the plasma of high B value is to be confined safely in the research of plasma fusion. So, the Reversed Field Pinch (RFP) plasma has been studied. RFP is stable pinch having self-reversal phenomenon that forms reversed field of itself, but its process of formation is unstable. Therefore, in this paper, we configured the stable RFP by supplying the radio-frequency rotating field just before the RFP is configured by self-reversal phenomenon. Moreover, when conductivity wall is used, toroidal configured by self-reversal phenomenon. Moreover, when conductivity wall is used, toroidal flux is subject to heavy fluctuation in case of high bias field compared with low bias field.

Improvement Study on Vertical Growth of Carbon Nanotubes and their Field Emission Properties at ICPCVD (유도결합형 플라즈마 화학기상증착법에서 탄소나노튜브의 수직성장과 전계방출 특성 향상 연구)

  • 김광식;류호진;장건익
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.15 no.8
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    • pp.713-719
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    • 2002
  • In this study, the vertically well-aligned CNTs were synthesized by DC bias-assisted inductively coupled plasma hot-filament chemical vapor deposition (ICPHFCVD) using radio-frequence plasma of high density and that CNTs were vertically grown on Ni(300 )/Cr(200 )-deposited glass substrates at 58$0^{\circ}C$. This system(ICPHFCVD) added to tungsten filament in order to get thermal decompound and DC bias in order to vertically grow to general Inductively Coupled Plasma CVD. The grown CNTs by ICPHFCVD were developed to higher graphitization and fewer field emission properties than those by general ICPCVD. In this system, DC bias was effect of vortical alignment to growing CNTs. The measured turn-on fields of field emission property by general ICPCVD and DC bias-assisted ICPHFCVD were 5 V/${\mu}{\textrm}{m}$ and 3 V/${\mu}{\textrm}{m}$, respectively.

Annealing Temperature Dependence of Exchange Bias Effect in Short Time Annealed NiFe/NiMn Bilayer Thin Film by FMR Measurement

  • Yoo, Yong-Goo;Park, Nam-Seok;Min, Seong-Gi;Yu, Seong-Cho
    • Journal of Magnetics
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    • v.10 no.4
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    • pp.133-136
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    • 2005
  • The NiMn/NiFe bilayer structure which was short time annealed in order to induce unidirectional anisotropy were studied as a function of annealing temperature. The maximum exchange bias field of NiMn/NiFe bilayer was presented at $250^{\circ}C$ after short time annealing process with no external field. The appearance of exchange bias was due to phase transformation of NiMn layer. In plane angular dependence of a resonance field distribution which measured by FMR was analysed as a combined effect of unidirectional anisotropy and uniaxial anisotropy. The resonance field and the line width from FMR measurement were also analysed with annealing temperature.

Bias Field Effect of SmCo Films on Soft Magnetic Properties of CoZrNb Films (SmCo박막의 바이어스자계가 CoZrNb박막의 연자성특성에 미치는 효과)

  • Shin, K.H.;Kim, Y.H.
    • Journal of the Korean Magnetics Society
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    • v.13 no.5
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    • pp.198-203
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    • 2003
  • To investigate whether the use of hard magnetic film is available to generate bias magnetic field for a magnetoimpedance sensor, the magnetic properties of SmCo hard magnetic films were investigated as a function of their compositions. The saturation magnetization decreased with Sm content increasing in SmCo films. And, the coercive force increased in the extent of Sm content of 28 at%, but decreased as Sm content increased moreover. The bias field effect of SmCo film to amorphous CoZrNb film was investigated with the magnetization corves, permeabilities, and magnetic domain structures of SmCo/CoZrNb multilayers. The bias field of about 60 Oe was observed in the film with 3 mm ${\times}$ 0.5 mm, which can be constructed as a MI sensor, and this result strongly indicates that the bias field generated from a hard magnetic film is adequate to enhance the sensitivity of a MI sensor with hard/soft magnetic multilayer structure.

The Payment Term Choice on E-marketplace: Focusing on Status Quo Bias and Anchoring Effect (무역거래알선사이트에서의 결제조건 선택: 현상유지편향과 정박효과를 중심으로)

  • Yoon Lee;Hong-joo Jung
    • Korea Trade Review
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    • v.46 no.1
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    • pp.23-38
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    • 2021
  • This paper investigated the preference change of payment terms in international trade along with counteroffer or first offer conditions of the other parties. Studies on trade payment terms have mainly focused on payment term determination factors such as firm size, product price level, country credit rate, etc. We tried to find other factors affecting payment terms choice, during the negotiation process. We applied behavioral economics theories such as 'Status Quo Bias' and 'Anchoring effect' to build our research model. To prove the existence of the above effects, we proceeded with field experiments to the exporting companies in Alibaba.com. Both 'Status Quo Bias' and 'Anchoring effect' were found in the field experiment. Most of the exporting companies preferred traditional payment methods to new payment methods. And an initial request for a low advance payment ratio led to a lower advance payment ratio. Also, the experience of using new payment methods could diminish status quo bias. This paper applied behavioral economics theories and field experiment methodology to the payment term studies in international trades. These attempts could contribute to expanding the diversity of methodology and scope of international trade studies.

Demagnetization Performance According to Vertical and Horizontal Magnetic Bias Fields

  • Kim, Young-Hak;Kim, Ki-Chan;Shin, Kwang-Ho;Yoon, Kwan-Seob;Yang, Chang-Seob
    • Journal of Magnetics
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    • v.16 no.4
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    • pp.453-456
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    • 2011
  • Demagnetization for a tube sample which was made of a galvanized steel sheet was performed by applying a magnetic field with a decrement to remove the remanent magnetization of the material. An orthogonal fluxgate magnetic field sensor was used to measure a magnetic field created from a ferromagnetic material. To evaluate the remanent magnetization, the measured magnetic fields were separated into two magnetic field components by the remnant magnetization and the induced one. The horizontal and the vertical bias fields should be controlled separately during demagnetization to remove the horizontal and the vertical components of the remanent magnetization of the tube sample.

Exchange Bias Coupling Depending on Uniaxial Deposition Field of Antiferromagnetic FeMn Layer

  • Lee, Sang-Suk;Hwang, Do-Guwn
    • Journal of Magnetics
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    • v.15 no.1
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    • pp.17-20
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    • 2010
  • The relationship between ferromagnet anisotropic magnetization and the antiferromagnet atomic spin configuration was investigated for various angles of the uniaxial deposition magnetic field of the FeMn layer in the Corning glass/Ta(5nm)/NiFe(7nm)/FeMn(25nm)/Ta(5nm) multilayer that was prepared by the ion beam sputter deposition. The exchange bias field ($H_{ex}$) obtained from the measurement of the easy-axis MR loop decreased to 40 Oe at the deposition field angle of $45^{\circ}$, and to 0 Oe at the angle of $90^{\circ}$. When the difference between the uniaxial axis between the ferromagnet NiFe and the antiferromagnet FeMn was $90^{\circ}$, the strong antiferromagnetic dipole moment of FeMn caused the weak ferromagnetic dipole moment of NiFe to rotate in the interface.