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Oishi, Daisuke*; Hayakawa, Hironori*; Akahama, Hiroshi*; Ikeda, Naoshi*; Kambe, Takashi*; Matsuo, Yoji*; Kimizuka, Noboru*; Kano, Jun*; Yoshii, Kenji
Ferroelectrics, 415(1), p.51 - 56, 2011/10
Times Cited Count:5 Percentile:25.35(Materials Science, Multidisciplinary)The variation of AC dielectric constant in the function of the DC magnetic fields was found in low oxygen vacant LuFeO single crystal in which the electric polarization arise from the polar charge ordering. These magneto-electric coupling should be explained by a novel mechanism where the boundary motion of the polar charge ordered domain is affected by the magnetic (spin) domain boundary motion.
Matsuo, Yoji*; Hoshiyama, Takuya*; Mori, Shigeo*; Yoshii, Kenji; Michiue, Yuichi*; Kambe, Takashi*; Ikeda, Naoshi*; Brown, F.*; Kimizuka, Noboru*
Japanese Journal of Applied Physics, 48(9), p.09KB04_1 - 09KB04_3, 2009/10
Times Cited Count:1 Percentile:5.3(Physics, Applied)We have investigated an average crystal structure and microstructures in LuFeTiO by the transmission electron microscopy (TEM), in combination with the dielectric measurements. In this work, high-qualitypolycrystalline samples of LuFeTiO were successfully synthesized in air by the conventional solid state reaction. The average crystal structure at room temperature is characterized by the hexagonal structure (space group: 6 cm). Dielectric measurements revealed that LuFeTiO shows broad dielectric dispersion around 570 K, which should originate from the formation of the polar domain structures on the nanometer scale.
Kuroda, Tomoko*; Fukuyama, Ryota*; Kitamura, Satoshi*; Matsuo, Yoji*; Ikeda, Naoshi*; Kambe, Takashi*; Agui, Akane; Kimizuka, Noboru*
no journal, ,
no abstracts in English
Maeda, Daisuke*; Fukuyama, Ryota*; Kitamura, Satoshi*; Funae, Takeshi*; Matsuo, Yoji*; Ikeda, Naoshi*; Kambe, Takashi*; Kimizuka, Noboru*; Yoshii, Kenji
no journal, ,
We have investigated the successive phase transition in YFeO, which shows charge-ordering-induced ferroelectricity below about 330 K. This material has been reported to show complex phase transitions below 330 K. In this work we have studied the structure and physical properties of YFeO synthesized in a variety of preparation conditions, and have found that slight changes of the conditions led to drastic alternations of physical properties. Details of the results will be shown at the conference.
Hayakawa, Hironori*; Kubota, Masato*; Oishi, Daisuke*; Akahama, Yuji*; Matsuo, Yoji*; Ikeda, Naoshi*; Kambe, Takashi*; Kimizuka, Noboru*; Yoshii, Kenji
no journal, ,
We have investigated the change of charge-ordered state in LuFeO caused by an applied electric field. The application of the field above a threshold led to a drastic decrease in resistivity; this behavior corresponds to the change of charge-ordered structure observed using synchrotron radiation. More details will be shown at the conference.
Oishi, Daisuke*; Hayakawa, Hironori*; Akahama, Yuji*; Funae, Takeshi*; Matsuo, Yoji*; Ikeda, Naoshi*; Kambe, Takashi*; Kimizuka, Noboru*; Yoshii, Kenji
no journal, ,
We have investigated the multiferroic behavior and the magnetic phase diagram of single-crystalline electronic ferroelectric LuFeO. Dielectric measurements under an applied magnetic field showed large magneto-capacitance at around room temperature. A complex magnetic phase diagram was obtained from detailed magnetic measurements below about room temperature. More details will be shown at the conference.
Fukuyama, Ryota*; Yoshii, Kenji; Kuroda, Tomoko*; Kitamura, Satoshi*; Funae, Takeshi*; Matsuo, Yoji*; Ikeda, Naoshi*; Kimizuka, Noboru*; Kambe, Takashi*
no journal, ,
We have investigated the physical properties of LuFeO, which has a related structure to the electronic ferroelectric RFeO (R: rare earths). Magnetic measurements showed that its magnetic transition temperature was about 260-270 K. Dielectric measurements showed that dielectric constants at room temperature were about 10000. This material also showed a magneto-dielectric effect at around room temperature, a result which is interesting from the viewpoints of both fundamental and applied science.
Matsumoto, Keisuke*; Matsuo, Yoji*; Oishi, Daisuke*; Akahama, Yuji*; Yoshii, Kenji; Hanasaki, Noriaki*; Kambe, Takashi*; Ikeda, Naoshi*; Kimizuka, Noboru*; Mori, Shigeo*
no journal, ,
We have investigated the charge-ordered structure and physical properties of YbFeMnO. Electron diffraction measurements showed a disappearance of charge-ordered structure of Fe ions by the Mn substitution. The Mn substitution also led to a monotonic decrease in magnetic transition temperature, low-temperature magnetization and dielectric constants. The results are explained in connection with several factors such as short-range ionic order.
Hoshiyama, Takuya*; Mori, Shigeo*; Matsuo, Yoji*; Funae, Takeshi*; Kambe, Takashi*; Ikeda, Naoshi*; Kimizuka, Noboru*; Yoshii, Kenji; Michiue, Yuichi*
no journal, ,
We have investigated the crystal structure and physical properties of RFeTiO(R=Lu,Yb). The samples were prepared by the solid-state reaction method in air. X-ray and electron diffraction measurements showed that the materials have the same crystal structure as that of multiferroic RMnO. Magnetic measurements showed the absence of magnetic transition below 400 K. Dielectric measurements showed the peak of dielectric constant above room temperature, suggesting a existence of ferroelectric phase transition at high temperatures.