http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
High Field ESR Measurements on One Dimensional Antiferromagnetic Zigzag Chain Systems
Hitoshi Ohta,Susumu Okubo,Kousuke Shiraki,Makoto Yoshida,Alexei A. Belik,Masaki Azuma 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.53 No.2
In order to study the dynamical properties of the S = 1/2 one-dimensional zigzag chain anti-ferromagnet PbCuP2O7, we performed high field electron spin resonance (ESR) measurements of powder and magnetically aligned samples of PbCuP2O7 by using pulsed magnetic fields up to 15 T in the temperature range from 1.7 to 265 K. Dynamical properties, such as the increases in the g-value and the linewidth at low temperature, are observed. By the aid of a direct numerical ESR calculation, the observed g-shift can be understood only by assuming the Dzyaloshinski-Moriya interaction in the system. This is a new approach to determine the Dzyaloshinski-Moriya interaction in a S = 1/2 one-dimensional antiferromagnet.
Ohta, Eisuke,Kobayashi, Hitoshi,Sakai, Atsushi,Matsui, Yasunori,Sato, Hiroyasu,Ikeda, Hiroshi Korean Society of Photoscience 2015 Rapid communication in photoscience Vol.4 No.2
Fluorescence (FL) properties of a novel donor-acceptor dyad, comprised of mesitylene and 1,4-dicyano-2-methylnaphthalene (DCMN) subunits connected by an ether linkage, were elucidated. The dyad in cyclohexane exhibits FL arising from an intramolecular exciplex. In the crystalline state, the dyad does not emit light from intra- and inter-molecular exciplexes but rather displays FL that is nearly equivalent to that of 2-methoxymethyl-substituted DCMN. However, the emission spectrum of the crystalline dyad contains a shoulder in the long wavelength region, suggesting that weak intercolumnar charge-transfer interactions take place between columns consisting of the mesitylene and DCMN subunits.
Nonmagnetic Impurity Effect of the S = 1/2 Spin Ladder System (pipdH)2Cu1−xZnxBr4
Chiori Yokoyama,Eiichi Matsuoka,Hitoshi Sugawara,Takahiro Sakurai,Weimin Zhang,Susumu Okubo,Hitoshi Ohta,Hikomitsu Kikuchi 한국물리학회 2013 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.62 No.12
We report the synthesis and the magnetic susceptibility of (pipdH)2Cu1−xZnxBr4(pipd=piperidinium), which is a nonmagnetic impurity-doped S = 1/2 spin ladder system. The sampleswere synthesized from a solution by using a slow evaporation method. Samples were confirmedto be in a single phase and to have the same crystal structure as the pure system (pipdH)2CuBr4by using X-ray diffraction measurements. To check the magnetic properties, we performed magneticsusceptibility and magnetization measurements with a superconducting quantum interferencedevice magnetometer. A plot of the inverse magnetic susceptibility indicates the presence of dominantantiferromagnetic coupling. The magnetic susceptibility shows a broad maximum due to lowdimensionality and a spin gap behavior related to the two-leg spin ladder at low temperature. Thespin gap and the Curie constants of Zn-doped samples, as estimated from an analysis of themagnetic susceptibility, monotonically decrease as the Zn concentration decreases. A nonmagneticimpurity of S = 1/2 spin ladder system affects the spin gap.
Magnetic Anisotropy of Tetragonal Rare-earth Compounds RRu2Al2B (R: Rare-earth Metals)
Eiichi Matsuoka,Yo Tomiyama,Kotaro Iwasawa,Hitoshi Sugawara,Takahiro Sakurai,Hitoshi Ohta 한국물리학회 2013 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.62 No.12
Recently, a new tetragonal compound CeRu2Al2B, which shows successive magnetic transitionsof antiferromagnetic and ferromagnetic orders was discovered. In this paper, the results of magnetizationmeasurements on magnetically-aligned powder sample of CeRu2Al2B were reported. Highly-anisotropic behaviors between the magnetizations along the easy and the hard directionswere observed. The anisotropic behavior of the magnetizations could be explained qualitativelyby considering the crystalline-electric-field scheme with the
Yuki Tokuda,Daichi Tsubokura,Eiji Ohmichi,Hitoshi Ohta 한국자기학회 2013 Journal of Magnetics Vol.18 No.2
Cantilever-detected high-frequency electron spin resonance (ESR) is a powerful method of sub-terahertz and terahertz ESR spectroscopy for a tiny magnetic sample at low temperature. In this technique, a small magnetization change associated with ESR transition is detected as deflection of a sample-mounted cantilever. So far, we have succeeded in ESR detection at 370 GHz using a commercial piezoresistive microcantilever. The spin sensitivity was estimated to ~10<SUP>12</SUP> spins/gauss. In order to further increase the sensitivity, we adopt a fiber-opticbased detection system using a Fabry-Perot interferometer in place of piezoresistive system. Fabry-Perot cavity is formed between an optical-fiber end and microcantilever surface, and a change in the interference signal, corresponding to the cantilever deflection, is sensitively detected. This system is suitable for low-temperature and high-magnetic-field experiments because of its compact setup and less heat dissipation. In this study, performance of Fabry-Perot interferometer is evaluated, and its application to cantilever-detected ESR measurement is described.