http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Growth-temperature-dependent Ferrimagnetism in Mn3Ga Thin Films
Wuwei Feng,신유리미,조성래,Dang Duc Dung 한국물리학회 2013 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.63 No.5
We report on the growth of and the modified ferrimagnetism in DO22-structured Mn3Ga thin films epitaxially grown on GaSb(001) substrate by using molecular beam epitaxy. We have observed that the magnetic properties strongly depend on the growth temperature. The net magnetic moments of the Mn3Ga films grown at 30 ◦C and 200 ℃ are 0.23 µB/Mn and 0.75 µB/Mn atom, respectively. The as-studied Mn3Ga film is found to exhibit a relatively small coercivity around 400 Oe, which differs greatly from the hard magnetic properties of bulk Mn3Ga.
Magneto-optic Kerr Effect and Magnetic Properties of Ferromagnetic Semiconducting MnGeAs2 Thin Films
최정용,Wuwei Feng,Weiqiang Mu,J. B. Ketterson,C.-C. Tsai,조성래 한국물리학회 2009 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.55 No.1
We have studied the magneto-optic Kerr effect (MOKE) and static magnetic properties of MnGeAs2 films grown by using molecular beam epitaxy (MBE) and prepared in different arsenic ambiences. Both reflection high energy electron diffraction (RHEED) and θ-2θ X-ray diffraction confirm epitaxial growth. We have observed the As pressure dependency in MOKE hysteresis and a well-defined rectangular MOKE hysteresis in the film grown at a 1.8 × 10−6 Torr As pressure. These As pressure dependent magnetic properties are related to defects in the MnGeAs2 films.
Epitaxial Growth and Magnetic Properties of Mn-Ga Thin Films on GaSb (001)
조성래,Wuwei Feng,Dang Duc Dung,Yooleemi Shin,Duong Van Thiet,Xian Hao 한국물리학회 2010 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.56 No.4
We report on the epitaxial stabilization of tetragonal DO22-type Mn3−δGa (δ= 0 to 2) films deposited on GaSb(001) by using a molecular beam epitaxy technique. The structural and the magnetic properties as functions of the Mn concentration are discussed. The growth orientation of Mn-Ga(114)//GaSb(001) caused the easy magnetocrystalline direction to be located in the film plane in our experiment, which differed from the ordinarily observed perpendicular magnetic-anisotropy of Mn3−δGa films. The increase in coercivity with increasing temperature for the MnGa film is possibly due to an increase in the anisotropy energy. The MnGa film exhibited an enhanced anisotropy energy with respect to Mn3Ga film. An increasing average saturation magnetization per Mn atom with decreasing Mn content was also observed, indicating a ferrimagnetic ordering with partially compensating moments of the two crystallographically different Mn sites in the DO22 structure.
Wang, Weihua,Feng, Wuwei,Yuan, Jiangyan,Pang, Ning,Zhao, Xiaoxue,Li, Meiyun,Bao, Zhidi,Zhu, Kun,Odkhuu, Dorj Elsevier 2018 PHYSICA B-CONDENSED MATTER - Vol.540 No.-
<P><B>Abstract</B></P> <P>Double perovskite La<SUB>2</SUB>Fe<SUB>2-x</SUB>Co<SUB>x</SUB>O<SUB>6</SUB> was prepared and studied. Orthorhombic and trigonal structures were obtained depend on the molar ratio of Fe to Co. Fe-rich sample demonstrate ferrimagnetic properties; with increasing content of Co, trigonal structure is favored and the net magnetic moment of sample decrease gradually to zero. Our experimental results were further supported by first-principle theoretical calculations and demonstrate that La<SUB>2</SUB>Fe<SUB>2-x</SUB>Co<SUB>x</SUB>O<SUB>6</SUB> is a new high <I>T</I> <SUB> <I>c</I> </SUB> ferromagnetic semiconductor with tunable magnetic properties and is thus a promising material for spintronics devices.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Phase-pure double perovskite La2Fe2-xCoxO6 was prepared. </LI> <LI> Orthorhombic and trigonal structures were obtained depending on the ratio of Fe to Co. </LI> <LI> La2Fe2-xCoxO6 is a new high Tc ferromagnetic semiconductor with tunable magnetic properties. </LI> <LI> Theoretical ab initio calculations further support our experimental results. </LI> </UL> </P>