Study of Surface Spin Wave by use of Variable Temperature Conversion Electron Spectrometer for Mossbauer Spectroscopy

变温转换电子能谱仪穆斯堡尔谱研究表面自旋波

• 批准号: 60540198
• 负责人: TAKETANI Hiroshi
• 金额: $ 1.15万
• 依托单位: Tokyo Institute of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1985
• 资助国家: 日本
• 起止时间: 1985 至 1986
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-60540198/
• 关键词: Variable Temperature; Conversion Electron; Mossbauer Spectroscopy; Iron Oxide Film; 表面スピン波

It was an aim of this study to measure the difference between a temperature dependence of magnetization at surface and that in bulk of the samples; <Fe_(1-x)O> (Wustite), <Fe_3O_4> (Magnetite) and <FeF_2> (Iron fluoride), by use of temperature variable conversion electron Mossbauer spectroscopy. The enriched <^(57)Fe> oxide thin film was made under the <O_2> partial pressure of <10^(-16.5)> atm. and at the temperature of 800 C. This film was observed to be composed of <Fe_3O_4> , <Fe_(1-x)O> and -Fe by use of a He + 10% <CH_4> proportional counter for Conversion Electron Mossbauer Spectroscopy. After then, Mossbauer spectra for the film have been measured with the electron spectrometer mentioned above. For 6.6 keV, 7.15keV and 7.3 keV, the spectra have been obtained at 5, 6 and 2 different temperatures, respectively. Although the statistics of these were not so satisfactory because the Mossbauer source used was not strong(30 mCi), the following results were obtained.1) This iron oxide film is composed of <Fe_3O_4> , <Fe_(1-x)O> and -Fe from surface to deeper region sequentially. 2) The transition temperature of <Fe_(1-x)O> is between 176 K and 206 K and the hyperfine field of <Fe_(1-x)O> nearly coincides with that of <Fe_3O_4> at lower temperature than 156 K. 3) It is observed that in 7.3 keV spectrum,measured at 78 K, there is a component of <Fe_3O_4> with the hyperfine field larger than those in the other energies at the same temperature.Nextly, the same measurements for <Fe_3O_4> enriched film will be done with the Mossbauer source stronger than the present in order to confirm the third result.

本文用变温转换电子穆斯堡尔谱测量了&lt;Fe_（1-x）O&gt;（Wustite）、（Magnetite）和（FeF）样品的表面磁化强度与体相磁化强度随温度变化的差异<Fe_3O_4><FeF_2>。在&lt;10^（-16.5）&gt; atm的分压下制备富集&lt;^（57）Fe&gt;氧化物薄膜<O_2>。并在800 ℃的温度下。用<Fe_3O_4>He + 10%正比计数管作转换电子穆斯堡尔谱，观察到该膜由&lt;Fe_（1-x）O&gt;和-Fe组成<CH_4>。然后用电子能谱仪测量了薄膜的穆斯堡尔谱。对于6.6keV、7.15keV和7.3keV，分别在5、6和2个不同温度下获得了谱。虽然由于穆斯堡尔源不强（30 mCi），这些统计数据不太令人满意，但得到以下结果：1）这种氧化铁膜<Fe_3O_4>从表面到深层依次由&lt;Fe_（1-x）O&gt;、-Fe组成。2)&lt;Fe_（1-x）O&gt;的转变温度在176 ~ 206 K之间，在低于156 K的温度范围内，超精细场与超精细场几乎一致<Fe_3O_4>。3)在78 K下测得的7.3keV能谱中，有一个<Fe_3O_4>超精细场分量比同温度下其它能量的分量大，<Fe_3O_4>为了证实第三个结果，我们将用比现在强的穆斯堡尔源对富集膜进行同样的测量。

项目成果

T.Toriyama;K.Ueoka: Hyperfine Interactions. 29. 1525-1528 (1986)

T.Toriyama；K.Ueoka：超精细交互。

T. Toriyama and K. Ueoka: "Improvement of S/N ratio of a proportional counter for Depth-selective Conversion Electron Spectroscopy" Hyperfine Interactions. 29. 1525-1528 (1986)

T. Toriyama 和 K. Ueoka：“深度选择性转换电子能谱正比计数器信噪比的改进”超精细交互。