| Project/Area Number |
06650025
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
Applied materials science/Crystal engineering
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| Research Institution | Kyusyu Institute of Technology |
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Principal Investigator |
MATSUSHITA Teruo Kyushu Institute of Technology, Faculty of Computer Science and Systems Engineering, Professor, 情報工学部, 教授 (90038084)
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| Co-Investigator(Kenkyū-buntansha) |
OTABE Edmund soji Kyushu Institute of Technology, Faculty of Computer Science and Systems Engineer, 情報工学部, 助手 (30231236)
FURUKAWA Shoji Kyushu Institute of Technology, Faculty of Computer Science and Systems Engineer, 情報工学部, 助教授 (30199426)
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| Project Period (FY) |
1994 – 1995
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| Project Status |
Completed (Fiscal Year 1995)
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| Budget Amount *help |
¥2,000,000 (Direct Cost: ¥2,000,000)
Fiscal Year 1995: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 1994: ¥1,500,000 (Direct Cost: ¥1,500,000)
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| Keywords | superconductivity / longitudinal magnetic field / motion of flux line / structure of electric field / Josephson's equation |
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| Research Abstract |
The structure of electric field on a surface of superconducting slab Pb-In specimens which carry a transport current under a parallel magnetic field is investigated. It turns out that the negative electric field opposed to the direction of applied current appears at a certain portion under a sufficiently high magnetic field and a certain pattern of the electric field is observed. However, the periodicity of the structure is not ascertained because of a shorter length of specimens than the structure determined from the ratio between the DC field and the self field of the current. It is found that the transverse electric field also appears in the resistive state and takes positive and negative values in correlation with the longitudinal electric field. Thus, it is concluded that the transverse electric field does not originate from the Hall effect but comes from the motion of flux lines as well as in the cylindrical superconducting specimen. As a result, the Josephson equation does not hold correct but it is theoretically shown that the electric field is described as E=B*v-gradphi, where B is the magnetic flux density and v is the velocity of flux lines. Here phi is not a simple electrostatic potential but is a potential which leads to the induced electric field due to the flux motion. While E*v gives rise to the negative electric field, the energy dissipation is associated only with-grad phi.
The differential resistivity on the whole specimen increases monotonically with increasing magnetic field and agrees qualitatively with the Bardeen-Stephen model under the transverse magnetic field.
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