Two-dimensional(2D) CrI_(3) is a ferromagnetic semiconductor with potential for applications in spintronics. However,its low Curie temperature(T_(c)) hinders realistic applications of CrI3. Based on first-principles c...Two-dimensional(2D) CrI_(3) is a ferromagnetic semiconductor with potential for applications in spintronics. However,its low Curie temperature(T_(c)) hinders realistic applications of CrI3. Based on first-principles calculations, 5d transition metal(TM) atom doping of CrI_(3)(TM@CrI_(3)) is a universally effective way to increase T_(c), which stems from the increased magnetic moment induced by doping with TM atoms. T_(c) of W@CrI_(3) reaches 254 K, nearly six times higher than that of the host CrI_(3). When the doping concentration of W atoms is increased to above 5.9%, W@CrI_(3) shows room-temperature ferromagnetism. Intriguingly, the large magnetic anisotropy energy of W@CrI_(3) can stabilize the long-range ferromagnetic order. Moreover, TM@CrI_(3) has a strong ferromagnetic stability. All TM@CrI_(3) change from a semiconductor to a halfmetal, except doping with Au atom. These results provide information relevant to potential applications of CrI_(3) monolayers in spintronics.展开更多
CuFe2O4 nanotube arrays with different outer diameters were synthesized in anodic aluminum oxide templates through sol-gel techniques followed by heating treatment processes. The morphology of the nanotube arrays was ...CuFe2O4 nanotube arrays with different outer diameters were synthesized in anodic aluminum oxide templates through sol-gel techniques followed by heating treatment processes. The morphology of the nanotube arrays was investigated by field emission scanning electron microscope and transmission electron microscopy, suggesting that the nanotube arrays are ordered and uniform. The X-ray diffraction results indicate that the crystal structure of the nanotube arrays is polycrystalline with a spinel-type structure. The measurements of magnetic properties indicate that CuFe2O4 nanotube arrays with outer diameter of 200 nm exhibit magnetic anisotropy with easy magnetization direction along the axis of nanotubes.展开更多
The Fel00-xMox （13≤x ≤25） alloy nanowire arrays are synthesized by electrodeposition of Fe^2＋and Mo^2＋ with different ionic ratios into the anodic aluminum oxide templates. The crystals of Fel00-xMox alloy nanow...The Fel00-xMox （13≤x ≤25） alloy nanowire arrays are synthesized by electrodeposition of Fe^2＋and Mo^2＋ with different ionic ratios into the anodic aluminum oxide templates. The crystals of Fel00-xMox alloy nanowires gradually change from polycrystalline phase to amorphous phase with the increase of the Mo content and the nanowires are of amorphous structure when the Mo content reaches 25 ate, which are revealed by the X-ray diffraction and the selected area electron diffraction patterns. As the Mo content increases, the magnetic hysteresis loops of Fel00-xMoz alloy nanowires in parallel to the nanowire axis are not rectangular and the slopes of magnetic hysteresis loops increase. Those results indicate that the magnetostatic interactions between nanowires and the magnetocrystalline anisotropy both have significant influences on the magnetization reversal process of the nanowire arrays.展开更多
史密斯拉菲堡（Chateau Smith Haut Lafitte）是我每次葡萄酒之旅的必经之路，坐落在格拉夫（Graves）北部经典产区佩萨克-雷奥良（Pessac—Leognan），与1855年梅多克列级名庄一级庄古堡奥比昂（Chateau Haut2Brion）同属一个产区。酒...史密斯拉菲堡（Chateau Smith Haut Lafitte）是我每次葡萄酒之旅的必经之路，坐落在格拉夫（Graves）北部经典产区佩萨克-雷奥良（Pessac—Leognan），与1855年梅多克列级名庄一级庄古堡奥比昂（Chateau Haut2Brion）同属一个产区。酒庄的主人丹尼尔·卡萨德（Daniel Cathiard）和夫人弗洛昂丝（Florence）曾是奥运滑雪运动员，而今是成功的商人。他们的经历本身就是一个追寻现实理想并获得成功的实践者的感人故事。展开更多
文摘Two-dimensional(2D) CrI_(3) is a ferromagnetic semiconductor with potential for applications in spintronics. However,its low Curie temperature(T_(c)) hinders realistic applications of CrI3. Based on first-principles calculations, 5d transition metal(TM) atom doping of CrI_(3)(TM@CrI_(3)) is a universally effective way to increase T_(c), which stems from the increased magnetic moment induced by doping with TM atoms. T_(c) of W@CrI_(3) reaches 254 K, nearly six times higher than that of the host CrI_(3). When the doping concentration of W atoms is increased to above 5.9%, W@CrI_(3) shows room-temperature ferromagnetism. Intriguingly, the large magnetic anisotropy energy of W@CrI_(3) can stabilize the long-range ferromagnetic order. Moreover, TM@CrI_(3) has a strong ferromagnetic stability. All TM@CrI_(3) change from a semiconductor to a halfmetal, except doping with Au atom. These results provide information relevant to potential applications of CrI_(3) monolayers in spintronics.
基金Funded by National Science Fund for Distinguished Young Scholars (No.50925103)the Key Project of Chinese Ministry of Education (No. 309027)+1 种基金the Fund for Academic Newcomer of PhD of Lanzhou Universitythe National Natural Science Foundation of China(No.11034004)
文摘CuFe2O4 nanotube arrays with different outer diameters were synthesized in anodic aluminum oxide templates through sol-gel techniques followed by heating treatment processes. The morphology of the nanotube arrays was investigated by field emission scanning electron microscope and transmission electron microscopy, suggesting that the nanotube arrays are ordered and uniform. The X-ray diffraction results indicate that the crystal structure of the nanotube arrays is polycrystalline with a spinel-type structure. The measurements of magnetic properties indicate that CuFe2O4 nanotube arrays with outer diameter of 200 nm exhibit magnetic anisotropy with easy magnetization direction along the axis of nanotubes.
基金Project supported by the National Science Fund for Distinguished Young Scholars,China(Grant No.50925103)the Key Program of the Chinese Ministry of Education(Grant No.309027)the Fund for Academic Newcomer of Ph.D.of Lanzhou University, China
文摘The Fel00-xMox （13≤x ≤25） alloy nanowire arrays are synthesized by electrodeposition of Fe^2＋and Mo^2＋ with different ionic ratios into the anodic aluminum oxide templates. The crystals of Fel00-xMox alloy nanowires gradually change from polycrystalline phase to amorphous phase with the increase of the Mo content and the nanowires are of amorphous structure when the Mo content reaches 25 ate, which are revealed by the X-ray diffraction and the selected area electron diffraction patterns. As the Mo content increases, the magnetic hysteresis loops of Fel00-xMoz alloy nanowires in parallel to the nanowire axis are not rectangular and the slopes of magnetic hysteresis loops increase. Those results indicate that the magnetostatic interactions between nanowires and the magnetocrystalline anisotropy both have significant influences on the magnetization reversal process of the nanowire arrays.
文摘史密斯拉菲堡（Chateau Smith Haut Lafitte）是我每次葡萄酒之旅的必经之路，坐落在格拉夫（Graves）北部经典产区佩萨克-雷奥良（Pessac—Leognan），与1855年梅多克列级名庄一级庄古堡奥比昂（Chateau Haut2Brion）同属一个产区。酒庄的主人丹尼尔·卡萨德（Daniel Cathiard）和夫人弗洛昂丝（Florence）曾是奥运滑雪运动员，而今是成功的商人。他们的经历本身就是一个追寻现实理想并获得成功的实践者的感人故事。
