Laser Spectroscopy of Fe-Co-Al-0 Granular Films

Fe-Co-Al-0 颗粒薄膜的激光光谱分析

基本信息

批准号：
17560586
负责人：
YOSHIHARA Akira
金额：
$ 2.24万
依托单位：
Ishinomaki Senshu University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2005
资助国家：
日本
起止时间：
2005 至 2006
项目状态：
已结题

项目摘要

2005 :1. We have examined superparamagnetic (SPM) excitations in a sputtered Co_<51>Al_<18>O_<31> film by Brillouin light scattering (BLS) at room temperature in magnetic fields of up to 6 kOe. We could observe transient behaviors from heavily damped spectra in disorder state below 0.5 kOe to the magnetostatic spin-wave (SW) spectra in the field-induced ferromagnetic state above 4.5 kOe. This is the very first BLS observation of the SPM excitations. We also confirmed that dipole coupling dominates the excitation frequencies. We have a plan to investigate the SPM excitations al low temperatures.2. We examined BLS from SWs in ferromagnetic Co_<78>Al_<18>O_<18>, Co_<66>Al_<11>O_<23> and Co_<63>Al_<13>O_<24> films in magnetic fields of up to 4.0 kOe at room temperature, and determined the magnetic constants including the exchange field H_<ex> for each film. Combining the exchange fields and the specific resistivities, we found an inverse-square law between the reisitivity ρ and the exchang … More e field H_<ex> : ρ_<Co>=22.1x H_<ex>^<-2> (μΩ.cm). Here, H_<ex> is in kOe unit.2006 :We consider that the inverse-square law is a characteristic magneto-electric property of the metal-nonmetal soft magnetic granular films. We selected Fe-Al-0 films as another model material, and measured BLS from the SWs at room temperature. We prepared Fe_<83>Al_<19>O_8, Fe_<76>Al_<12>O_<12>, Fe_<64>Al_<10>O_<17> and Fe_<62>Al_<19>O_<19> films in this study. Again, we obtained BLS spectra from SWs and determined their frequencies as a function of the magnetic field. We determined the exchange fields, and confirmed the inverse-square law given by ρ_<Fe>=30.3 x H_<ex>^<-2> (μΩ.cm) for the Fe-Al-O films.In this two years project we have obtained two important and quite new results. (1) We have clearly shown that inter-granule exchange coupling really exists in soft ferromagnetic nano-granular films. (2) Now it is possible to determine the exchange field constant of the TM-Al-0 (TM=Fe, Co) granular films through resistivity measurement. Less

2005：1。我们已经检查了溅射的CO_ <51> Al_ <18> O_ <31>在室温下，在室温下，胶片的超顺磁性（SPM）兴奋，摄影（BLS）在高达6 koe的磁场中。我们可以观察到低于0.5 KOE的无序状态下的严重阻尼光谱的瞬态行为，到磁性自旋波（SW）光谱，在野外诱导的铁磁状态下，高于4.5 KOE。这是对SPM兴奋的最初观察。我们还证实，偶极耦合主导了兴奋频率。我们有一个计划调查SPM兴奋的低温2。我们检查了来自Ferromagnetic Co_ <78> al_ <18> O_ <18>的SWS的BLS，CO_ <66> Al_ <11> O_ <11> O_ <23>和CO_ <63> Al_ <13> O_ <13> O_ <24>在室温下最高4.0 KOE的磁场中的胶卷，并确定了包括Exchange Field常数的4.0 KOE，并确定了每种磁场H____ <ex>。结合了交换场和特定的抗性，我们发现了重新固定ρ与交换之间的逆方法律……更多e Field H_ <ex>：ρ_<co> = 22.1x H_ <ex>^<-2>（μω.cm）。在这里，H_ <ex>在KOE单元中。2006：我们认为，反方定律是金属非金属软磁性颗粒膜的特征磁电特性。我们选择了Fe-Al-0膜作为另一种型号材料，并在室温下从SWS测量了BLS。我们准备了Fe_ <83> Al_ <19> O_8，Fe_ <76> Al_ <12> O_ <12>，Fe_ <64> Al_ <10> O_ <10> O_ <17>和Fe_ <62> Al_ <19> O_ <19> O_ <19>在这项研究中。同样，我们从SWS获得了BLS光谱，并确定其频率是磁场的函数。我们确定了交换场，并确认了ρ_<fe> = 30.3 x H_ <ex>^<-2>（μΩ.cm）的反向平方法。（1）我们清楚地表明，颗粒间交换耦合确实存在于软铁磁纳米粒状膜中。（2）现在可以通过电阻率测量来确定TM-AL-0（TM = Fe，CO）颗粒膜的交换场常数。较少的