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Ishikado, Motoyuki; Nagai, Yuki; Kodama, Katsuaki; Kajimoto, Ryoichi; Nakamura, Mitsutaka; Inamura, Yasuhiro; Wakimoto, Shuichi; Nakamura, Hiroki; Machida, Masahiko; Suzuki, Katsuhiro*; et al.
Physical Review B, 84(14), p.144517_1 - 144517_5, 2011/10
Times Cited Count:26 Percentile:70.69(Materials Science, Multidisciplinary)We performed inelastic neutron scattering on a powder sample of iron-based superconductor BaFe(AsP) with = 30 K. Although this system is expected to have line nodes in its superconducting order parameter, we have observed spin resonance at the same scattering vector as that appeared in the -wave iron-based superconductors without line nodes. Moreover, the resonance enhancement, which can be a measure of the area of sign reversal between the hole and electron Fermi surfaces (FSs), is comparable to those without line nodes. These facts indicate that the sign reversal between the FSs is still dominant in this system, and the line nodes should create only limited area of sign-reversal on a single FS. Hence the system can hold higher Tc than the other iron-based superconductors with nodal symmetry, such as LaFePO and KFeAs ( 10 K).
Son, N. T.*; Hemmingsson, C. G.*; Paskova, T.*; Evans, K. R.*; Usui, Akira*; Morishita, Norio; Oshima, Takeshi; Isoya, Junichi*; Monemar, B.*; Janzn, E.*
Physical Review B, 80(15), p.153202_1 - 153202_4, 2009/10
Times Cited Count:40 Percentile:79.94(Materials Science, Multidisciplinary)GaN samples were irradiated with electrons of 2 MeV at 110/cm, and electron spin resonance (ESR) was measured at 77 K. As a result, four defect signals which are labeled D1 to D4 were observed. The D2 signal was identified to be negatively charged gallium vacancy - oxygen pair from the details studies of N hf structure.
Ishikado, Motoyuki; Nagai, Yuki; Kodama, Katsuaki; Kajimoto, Ryoichi; Nakamura, Mitsutaka; Inamura, Yasuhiro; Mizuno, Fumio; Wakimoto, Shuichi; Nakamura, Hiroki; Machida, Masahiko; et al.
no journal, ,
Three years have passed since the discovery of iron-based superconductors, its maximum superconducting transition temperature () is 55 K, resulting in second highest material system next to cuprate high- superconductors. Among various material systems in iron-based superconductors, we have systematically studied on LaFeAsOF (=28 K) of first discovered system and BaFe(As,P) which have recently attracted tremendous attention by the discovery of line nodes in its order parameter. In the session, we present recent results on "spin fluctuation and superconductivity on LaFePO", and "symmetry of order parameter on BaFe(As,P) by inelastic neutron scattering" studied by the chopper spectrometer 4SEASONS (J-PARC).
Ishikado, Motoyuki; Nagai, Yuki; Kodama, Katsuaki; Kajimoto, Ryoichi; Nakamura, Mitsutaka; Inamura, Yasuhiro; Wakimoto, Shuichi; Nakamura, Hiroki; Machida, Masahiko; Suzuki, Katsuhiro*; et al.
no journal, ,
In this study, we have performed inelastic neutron scattering measurement on 36g powder sample of optimally-doped BaFe(As,P) whose superconducting order parameter is expected to have line node by Fermi chopper spectrometer 4SEASONS in J-PARC. Unexpectedly, we have observed spin resonance at same -position and nearly identical resonance enhancement ration to other iron-based superconducctors with fully-gapped -wave. We will discuss about the possible superconducting gap symmetry based on our experimental results.
Ishikado, Motoyuki; Kodama, Katsuaki; Wakimoto, Shuichi; Kajimoto, Ryoichi; Nakamura, Mitsutaka; Inamura, Yasuhiro; Mizuno, Fumio; Nagai, Yuki; Nakamura, Hiroki; Machida, Masahiko; et al.
no journal, ,
Among various iron-based superconductors, we have systematically studied on LaFeAsOF (=28 K) and BaFe(As,P) (=31 K) by the Fermi chopper spectrometer 4SEASONS (J-PARC). We will discuss the possible relation between high- superconductivity and magnetic fluctuation based on our inelastic neutron scattering results.
Ishikado, Motoyuki; Kodama, Katsuaki; Wakimoto, Shuichi; Kajimoto, Ryoichi; Nakamura, Mitsutaka; Inamura, Yasuhiro; Nagai, Yuki; Nakamura, Hiroki; Machida, Masahiko; Suzuki, Katsuhiro*; et al.
no journal, ,
In this study, we performed inelastic neutron scattering measurement on 36g polycrystalline powder sample of optimally-doped BaFe(AsP) using a Fermi chopper spectrometer 4SEASONS in J-PARC. We observed strong spin resonance at the same -position similar to those of other iron-based superconductors with fully-gapped -wave. We will discuss about the possible superconducting gap symmetry and what causes relatively high- of this material based on our inelastic neutron scattering results.
Ishikado, Motoyuki; Nagai, Yuki; Kodama, Katsuaki; Kajimoto, Ryoichi; Nakamura, Mitsutaka; Inamura, Yasuhiro; Mizuno, Fumio; Wakimoto, Shuichi; Nakamura, Hiroki; Machida, Masahiko; et al.
no journal, ,
We report systematic studies on Fe-based superconductors LaFeAsOF ( =28 K) and BaFe(As,P) ( =31 K) by using inelastic neutron scattering measurement.
Ishikado, Motoyuki; Nagai, Yuki; Kodama, Katsuaki; Kajimoto, Ryoichi; Nakamura, Mitsutaka; Inamura, Yasuhiro; Wakimoto, Shuichi; Nakamura, Hiroki; Machida, Masahiko; Suzuki, Katsuhiro*; et al.
no journal, ,
In this study, we performed inelastic neutron scattering measurement on 36g polycrystalline powder sample of optimally-doped BaFe(As,P) using Fermi chopper spectrometer 4SEASONS in J-PARC. Unexpectedly, we observed spin resonance at the same -position and nearly identical resonance enhancement ratio to other iron-based superconductors with fully-gapped -wave. We will discuss about the possible superconducting gap symmetry based on our inelastic neutron scattering experiment and theoretical calculations.
Ishikado, Motoyuki; Kodama, Katsuaki; Wakimoto, Shuichi; Kajimoto, Ryoichi; Nakamura, Mitsutaka; Inamura, Yasuhiro; Mizuno, Fumio; Nagai, Yuki; Nakamura, Hiroki; Machida, Masahiko; et al.
no journal, ,
We have systematically studied nodal iron-based superconductor LaFePO (=5 K) and BaFe(As,P) (=30 K) by using Fermi chopper spectrometer 4SEASONS (J-PARC) and Triple Axis Spectrometer (TAS-1) at JRR-3. In the session, we will discuss the relation between superconductivity and spin fluctuation.
Nakayama, Naoto; Yatsuda, Kazumi; Hamazaki, Masaaki; Usui, Toshihide; Nakada, Akira
no journal, ,
no abstracts in English
Hamazaki, Masaaki; Mori, Airi; Abe, Haruka; Goibuchi, Shota; Iwasa, Atsutoshi; Ishida, Keiichi; Usui, Toshihide; Eguchi, Kazutoshi; Nakada, Akira
no journal, ,
no abstracts in English