Measurement of electron spin flip-flop time
Project/Area Number |
59540202
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Research Category |
Grant-in-Aid for General Scientific Research (C)
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Allocation Type | Single-year Grants |
Research Field |
物性一般(含極低温・固体物性に対する理論)
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Research Institution | Shiga University |
Principal Investigator |
MURAMOTO Takao Faculty of Education, Shiga University, Professor, 教育学部, 教授 (80024925)
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Co-Investigator(Kenkyū-buntansha) |
TAKAGI Yoshihiro Institute of Molecular Science, Assistant, 助手 (80106161)
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Project Period (FY) |
1984 – 1986
|
Project Status |
Completed (Fiscal Year 1986)
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Budget Amount *help |
¥2,100,000 (Direct Cost: ¥2,100,000)
Fiscal Year 1986: ¥200,000 (Direct Cost: ¥200,000)
Fiscal Year 1985: ¥600,000 (Direct Cost: ¥600,000)
Fiscal Year 1984: ¥1,300,000 (Direct Cost: ¥1,300,000)
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Keywords | Cross relaxation time / Flip-flop time / Ruby / Optical hole burning / Homogeneous line width / Optical labeling technique / ブロッホ方程式 |
Research Abstract |
We have measured the flip-flop time of electron spins in the (+1/2)sublevels of the ground state <^4A_2> of <Cr^(3+)> in ruby. (Phys.Rev.B34.1972,'86) It is the first experiment in the world to measure directly the flip-flop time of a two-level elctron spin system. In this experiment, we used the method of optical labeling, which is proposed and examined by us in the same electron spin system. (Phys,Rev. B30 2983,'84) It is about 10 sec ( 0.05 wt% ) at the applied magnetic fields, higher than 500 Oe. It is longer than the reported value by A.Szabo obtained by indirect measurment. The cause of the difference has never been understood. We need much more precise measurements of concentration and magnetic field dependence. We also investigated the theoretical calculation of cross relaxation time in dilute spin system in solids.(Phys. Rev.B29.6043,'84) We porposed the time dependence of the spin flip-flop time, which will be proportional to <t^(-1/2)> . Theoretical and experimental investigation to show that Bloch equations to describe a two-level spin system are not always correct. In the saturation and the shape of homogeneous line broadening, differences between the experimental results and the theoretical anticipations become clear. (Optics Commun.51,163,'84) The cause of the differences is attributed to non-pure two level system. which is accompanied by many sublevels due to superhyperfyne interaction between surrounding paramagnetic nuclei. We have measured homogeneous line broad-ening of -components of <R_1> line in a dilute ruby at applied magnetic fileds and results are explained by the same idea reported above.
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Report
(1 results)
Research Products
(10 results)