Nonlinear Optical Spectroscopy on One-Dimensional Excitons in Silicon Polymer, Polysilane. (9999)
Hasegawa, T., Iwasa, Y., Sunamura, H., Koda, T., Tokura, Y.
#L027243 The nine independent stiffness constants of injection-molded tensile bars of poly(phenylene sulfide) reinforced with 30 and 40% by weight of carbon or glass fibers have been measured by...
Resonance Enhancement Effect in Non-Linear Optical Susceptibility of Polysilanes. (9999)
Iwasa, Y., Hasegawa, T., Koda, T., Tokura, Y., Tachibana, H.
We have investigated the \X(3)(-3 omega; omega, omega, omega)\ spectra of polysilane films by means of third-harmonic generation. The fundamental photon energy is scanned from 0.56 to 2.2 eV. The...
Dispersion relation in the Third-Order Electric Susceptibility for Polysilane Film. (9999)
Kishida, H., Hasegawa, T., Iwasa, Y., Koda, T., Tokura, Y.
FOUND TO BE IN GOOD
Quantitative analysis of electronic transport through weakly-coupled metal/organic interfaces (2008)
Molinari, A. S., Lezama, I. Gutierrez, Parisse, P., Takenobu, T., Iwasa, Y., Morpurgo, A. F.
Using single-crystal transistors, we have performed a systematic experimental study of electronic transport through oxidized copper/rubrene interfaces as a function of temperature and bias. We find...
Yokomizo, H., Haccou, P., Iwasa, Y.
Alien species are often a major threat to native species. We consider optimal conservation strategies for a population whose viability is affected both by an alien species (such as a competitor, a...
Low-energy excitations in electron-doped metal phthalocyanine from NMR in Li$_{0.5}$MnPc (2006)
Filibian, M., Carretta, P., Miyake, T., Taguchi, Y., Iwasa, Y.
$^7$Li and $^1$H NMR and magnetization measurements in \lpc (Pc$\equiv$C$_{32}$H$_{16}$N$_8$), recently proposed as a strongly correlated metal, are presented. Two different low-frequency dynamics...
Ferroelectric polarization flop in a frustrated magnet MnWO$_4$ induced by magnetic fields (2006)
Taniguchi, K., Abe, N., Takenobu, T., Iwasa, Y., Arima, T.
The relationship between magnetic order and ferroelectric properties has been investigated for MnWO$_4$ with long-wavelength magnetic structure. Spontaneous electric polarization is observed in an...
Hall effect of quasi-hole gas in organic single-crystal transistors (2005)
Takeya, J., Tsukagoshi, K., Aoyagi, Y., Takenobu, T., Iwasa, Y.
Hall effect is detected in organic field-effect transistors, using appropriately shaped rubrene (C42H28) single crystals. It turned out that inverse Hall coefficient, having a positive sign, is close...
Regularity in the intratube interaction in double-wall carbon nanotubes (2005)
Arvanitidis, J., Christofilos, D., Papagelis, K., Takenobu, T., Iwasa, Y., Kataura, H., ...
High pressure Raman experiments were performed on bundled double wall carbon nanotubes (DWCNTs). We observe peculiar regularity in the strength of the inner-outer tube (intratube) interaction, which...
Noro, S, Chang, HC, Takenobu, T, Murayama, Y, Kanbara, T, Aoyama, T, ...
Pressure screening in the interior of primary shells in double-wall carbon nanotubes (2004)
Arvanitidis, J., Christofilos, D., Papagelis, K., Andrikopoulos, K. S., Takenobu, T., Iwasa, Y., ...
The pressure response of double-wall carbon nanotubes has been investigated by means of Raman spectroscopy up to 10 GPa. The intensity of the radial breathing modes of the outer tubes decreases...
Takeya, J., Nishikawa, T., Takenobu, T., Kobayashi, S., Goldmann, C., Krellner, C., ...
The surface conductivity is measured by a four-probe technique for pentacene and rubrene single-crystals laminated on polarized and nearly unpolarized molecular monolayers with application of...
$^{11}$B NMR study of pure and lightly carbon doped MgB$_2$ superconductors (2004)
Karayanni, M., Papavassiliou, G., Pissas, M., Fardis, M., Papagelis, K., Prassides, K., ...
We report a $^{11}$B NMR line shape and spin-lattice relaxation rate ($1/(T_1T)$) study of pure and lightly carbon doped MgB$_{2-x}$C$_{x}$ for $x=0$, 0.02, and 0.04, in the vortex state and in...
Electronic transport through electron-doped Metal-Phthalocyanine Materials (2004)
Craciun, M. F., Rogge, S., Margadonna, S., Prassides, K., Iwasa, Y., ...
We report an insulator-metal-insulator transition in films of five metal phthalocyanines (MPc) doped with alkali atoms. Electrical conduction measurements demonstrate that increasing the alkali...
Sasaki, T., Ito, I., Yoneyama, N., Kobayashi, N., Hanasaki, N., Tajima, H., ...
The polarized optical reflectance spectra of the quasi two dimensional organic correlated electron system $\kappa$-(BEDT-TTF)$_{2}$Cu[N(CN)$_{2}$]$Y$, $Y =$ Br and Cl are measured in the infrared...
Utaka, T, Al-Drees, SA, Ueda, J, Iwasa, Y, Takeguchi, T, Kikuchi, R, ...
muSR study of carbon-doped MgB2 superconductors (2002)
Papagelis, K., Arvanitidis, J., Prassides, K., Schenck, A., Takenobu, T., Iwasa, Y.
The evolution of the superconducting properties of the carbon-doped MgB2 superconductors, MgB(2-x)Cx (x= 0.02, 0.04, 0.06) have been investigated by the transverse-field muon spin rotation (TF-muSR)...
Evidence for Insulating Behavior in the Electric Conduction of (NH$_3$)K$_3$C$_{60}$ Systems (2002)
Kitano, H., Matsuo, R., Miwa, K., Maeda, A., Takenobu, T., Iwasa, Y., ...
Microwave study using cavity perturbation technique revealed that the conductivity of antiferromagnet (NH$_3$)K$_{3-x}$Rb$_x$C$_{60}$ at 200K is already 3-4 orders of magnitude smaller than those of...
Survey of the State-of-the-Art of Miniature Cryocoolers for Superconductive Devices. (2002)
This document presents the results of a survey of the state-of-the-art as applied to cryocoolers to cool small superconducting devices. The survey included visits to over 100 facilities involved in...
Evidence for Spin-Singlet Superconductivity in Layered MgB2 (2001)
Tou, H., Ikejiri, H., Maniwa, Y., Ito, T., Takenobu, T., Prassides, K., ...
This paper has been withdrawn by the authors, because of serious experimental problems.
Intralayer Carbon Substitution in the MgB2 Superconductor (2001)
Takenobu, T., Ito, T., Chi, Dam H., Prassides, K., Iwasa, Y.
We report that the ternary MgB2-xCx compounds adopt an isostructural AlB2-type hexagonal structure in a relatively small range of nominal carbon concentration, x
Compressibility of the MgB2 Superconductor (2001)
Prassides, K., Iwasa, Y., Ito, T., Chi, D. H., Uehara, K., Nishibori, E., ...
Considerable excitement has been caused recently by the discovery that the binary boride system with stoichiometry MgB2 is superconducting at the remarkably high temperature of 39 K (1). This...
Pressure dependence of Tc in the MgB2 superconductor as probed by resistivity measurements (2001)
Saito, E., Taknenobu, T., Ito, T., Iwasa, Y., Prassides, K.
High-pressure resistivity experiments were performed on the recently discovered superconductor, MgB2. Tc decreases quasi-linearly with applied pressure to 1.4 GPa at a rate of -2.0(1) K/GPa, which is...
Vibrational spectroscopy of superconducting MgB2 by neutron inelastic scattering (2001)
Muranaka, T, Margadonna, S, Maurin, I, Brigatti, K, Colognesi, D, Prassides, K, ...
Raman Scattering Study of Ba-doped C60 with t1g States (1999)
Chen, X. H., Taga, S., Iwasa, Y.
Raman spectra are reported for Ba doped fullerides, BaxC60(x=3,4,and 6). The lowest frequency Hg modes split into five components for Ba4C60 and Ba6C60 even at room temperature, allowing us a...
Anomalous Raman shift in the ternary fullerides with t1g states (1999)
Chen, X. H., Takenobu, T., Muro, T., Fudo, H., Iwasa, Y.
Raman shift dependence of charge transfer is studied in the two fulleride families of AxBa3C60 (x=0,3; A=K,Rb) and KxSm2.75C60 (x=0,3.25). It is found that the Raman spectra are essentially identical...
Structure and properties of a novel fulleride Sm6C60 (1999)
Chen, X. H., Liu, Z. S., Li, S. Y., Dam, H. C., Iwasa, Y.
A novel fulleride Sm6C60 has been synthesized using high temperature solid state reaction. The Rietveld refinement on high resolution synchrotron X-ray powder diffraction data shows that Sm6C60 is...
Structure and Superconductivity in Alkali-Ammonia Complex Fullerides (1997)
Iwasa, Y., Shimoda, H., Miyamoto, Y., Mitani, T., Maniwa, Y., Zhou, O., ...
Alkali ammonia complex fullerides form a rich variety of compounds with unique structural and electronic properties. Intercalation of NH3 into K3C60 produces orthorhombic NH3C60, which undergoes a...
Metal-insulator transition in ammoniated K3C60 (1996)
Iwasa, Y., Shimoda, H., Palstra, T.T.M., Maniwa, Y., Zhou, O., Mitani, T.
Magnetic susceptibility, electron spin resonance, and 13C nuclear-magnetic-resonance data on NH3K3C60 reveal that NH3K3C60 is a narrow-band metal with a transition to an insulating ground state at 40...
Superconductivity at 40K in Cesium Doped C60 (1995)
Palstra, T.T.M., Zhou, O., Iwasa, Y., Sulewski, P.E., Fleming, R.M., Zegarski, B.R.
We report superconductivity in Cs3C60 at 40K using ac susceptibility measurements under hydrostatic conditions up to 15 kbar. Cs3C60 was prepared by reaction of C60 with Cs in liquid ammonia,...
Structural and electronic properties of (NH3)xK3C60 (1995)
Zhou, O., Palstra, T.T.M., Iwasa, Y., Fleming, R.M., Hebard, A.F., Sulewski, P.E., ...
We have investigated the synthesis, structure, and electronic properties of (NH3)xK3C60 by exposing preformed K3C60 to NH3 vapor. Measurements were made on bulk powders and films with a variety of...
32 TESLA HYBRID MAGNET SYSTEM (1984)
Leupold, M., Iwasa, Y., Weggel, R.
The paper describes the design and construction of a hybrid magnet system to generate 32T with 9MW of electrical power. The system consists of an 11T niobium-titanium superconducting magnet, a...
32 TESLA HYBRID MAGNET SYSTEM (1984)
Leupold, M., Iwasa, Y., Weggel, R.
The paper describes the design and construction of a hybrid magnet system to generate 32T with 9MW of electrical power. The system consists of an 11T niobium-titanium superconducting magnet, a...
32 TESLA HYBRID MAGNET SYSTEM (1984)
Leupold, M., Iwasa, Y., Weggel, R.
The paper describes the design and construction of a hybrid magnet system to generate 32T with 9MW of electrical power. The system consists of an 11T niobium-titanium superconducting magnet, a...
Evolutionarily Stable Mutation Rate in a Periodically Changing Environment
Ishii, K., Matsuda, H., Iwasa, Y., Sasaki, A.
Evolution of mutation rate controlled by a neutral modifier is studied for a locus with two alleles under temporally fluctuating selection pressure. A general formula is derived to calculate the...
The Evolution of Genomic Imprinting
Mochizuki, A., Takeda, Y., Iwasa, Y.
In some mammalian genes, the paternally and maternally derived alleles are expressed differently: this phenomenon is called genomic imprinting. Here we study the evolution of imprinting using...
The evolution of X-linked genomic imprinting.
We develop a quantitative genetic model to investigate the evolution of X-imprinting. The model compares two forces that select for X-imprinting: genomic conflict caused by polygamy and sex-specific...
Evolutionarily Stable Mutation Rate in a Periodically Changing Environment
Ishii, K., Matsuda, H., Iwasa, Y., Sasaki, A.
Evolution of mutation rate controlled by a neutral modifier is studied for a locus with two alleles under temporally fluctuating selection pressure. A general formula is derived to calculate the...
The Evolution of Genomic Imprinting
Mochizuki, A., Takeda, Y., Iwasa, Y.
In some mammalian genes, the paternally and maternally derived alleles are expressed differently: this phenomenon is called genomic imprinting. Here we study the evolution of imprinting using...
The evolution of X-linked genomic imprinting.
We develop a quantitative genetic model to investigate the evolution of X-imprinting. The model compares two forces that select for X-imprinting: genomic conflict caused by polygamy and sex-specific...