Manipulating spin spatial splitter in a δ-doped semiconductor nanostructure with zero average magnetic field

Multi-coil magnetic stimulation has advantages over single-coil magnetic stimulation, such as more accurate targeting and larger stimulation range. In this paper, a 4 × 4 array multichannel magnetic stimulation system based on a submillimeter planar square spiral coil is proposed. The effects of multiple currents with different directions on the electromagnetic field strength and the focusing zone of the array-structured magnetic stimulation system are studied. The spatial distribution characteristics of the electromagnetic field are discussed. In addition, a method is proposed that can predict the spatial distributions of the electric and magnetic fields when currents in different directions are applied to the array-structured magnetic stimulation system. The study results show that in the section of z = 2 μm, the maximum and average magnetic field strengths of the array-structured magnetic stimulation system are 6.39 mT and 2.68 mT, respectively. The maximum and average electric field strengths are 614.7 mV/m and 122.82 mV/m, respectively, where 84.39% of the measured electric field values are greater than 73 mV/m. The average magnetic field strength of the focusing zone, i.e., the zone in between the two coils, is 3.38 mT with a mean square deviation of 0.18. Therefore, the array-structured multi-channel magnetic stimulation system based on a planar square spiral coil can have a small size of 412 μm × 412 μm × 1.7 μm, which helps improving the spatial distribution of electromagnetic field and increase the effectiveness of magnetic stimulation. The main contribution of this paper is a method for designing multichannel micro-magnetic stimulation devices.

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Spin spatial splitter based on a magnetic nanostructure with zero average magnetic field

Applied Surface Science ◽

10.1016/j.apsusc.2014.06.019 ◽

2014 ◽

Vol 313 ◽

pp. 545-548 ◽

Cited By ~ 14

Author(s):

Xu-Hui Liu ◽

Gui-Lian Zhang ◽

Yong-Hong Kong ◽

Ai-Hua Li ◽

Xi Fu

Keyword(s):

Magnetic Field ◽

Average Magnetic Field ◽

Magnetic Nanostructure

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General Formulas for the Average Magnetic Field at a Receiving Circular-Loop Antenna Placed Arbitrarily to a Radiating Loop

IEEE Transactions on Instrumentation and Measurement ◽

10.1109/tim.1984.4315229 ◽

1984 ◽

Vol 33 (4) ◽

pp. 307-310

Author(s):

Hiroshi Nakane

Keyword(s):

Magnetic Field ◽

Loop Antenna ◽

Circular Loop ◽

Average Magnetic Field

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Optimization of a Two-Layer 3D Coil Structure with Uniform Magnetic Field

Wireless Power Transfer ◽

10.1155/2021/6303628 ◽

2021 ◽

Vol 2021 ◽

pp. 1-11

Author(s):

Davor Vinko ◽

Domagoj Bilandžija ◽

Vanja Mandrić Radivojević

Keyword(s):

Magnetic Field ◽

Field Strength ◽

Magnetic Field Strength ◽

Field Distribution ◽

Uniform Magnetic Field ◽

Optimization Method ◽

Magnetic Field Distribution ◽

Wireless Power ◽

Average Magnetic Field ◽

Coil Structure

Conventional magnetically coupled resonant wireless power transfer systems are faced with resonant frequency splitting phenomena and impedance mismatch when a receiving coil is placed at misaligned position. These problems can be avoided by using uniform magnetic field distribution at receiving plane. In this paper, a novel 3D transmitting coil structure with improved uniform magnetic field distribution is proposed based on a developed optimization method. The goal is to maximize the average magnetic field strength and uniform magnetic field section of the receiving plane. Hence, figures of merit (FoM1 and FoM2) are introduced and defined as product of average magnetic field strength and length or surface along which uniform magnetic field is generated, respectively. The validity of the optimization method is verified through laboratory measurements performed on the fabricated coils driven by signal generator at operating frequency of 150 kHz. Depending on the allowed ripple value and predefined coil proportions, the proposed transmitting coil structure gives the uniform magnetic field distribution across 50% to 90% of the receiving plane.

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