Magnetism and superconductivity in single crystals $Eu_{1-x}Sr_xFe_{2-y}Co_{y}As_2$ (2009)
Zheng, Q. J., He, Y., Wu, T., Wu, G., Chen, H., Ying, J. J., ...
We systematically studied the transport properties of single crystals of $Eu_{1-x}Sr_xFe_{2-y}$Co$_{y}As_2$. Co doping can suppress the spin-density wave (SDW) ordering and induces a superconducting...
Study of Electron Spin Resonance on single crystals $EuFe_{2-x}Co_{x}As_2$ (2009)
Ying, J. J., Wu, T., Zheng, Q. J., He, Y., Wu, G., Li, Q. J., ...
The temperature dependence of electron spin resonance (ESR) was studied in $EuFe_{2-x}Co_{x}As_2 $ (x = 0.0, 0.067, 0.1, 0.2, 0.25, 0.285, 0.35, 0.4 and 0.5). The ESR spectrum of all the samples...
Xie, Y. L., Liu, R. H., Wu, T., Wu, G., Song, Y. A., Tan, D., ...
We have successfully prepared the new layered oxypnictides $Sr_4Sc_2O_6M_2As_2$ (M=Fe and Co). They adopt the tetragonal structure, being the same as that of $Sr_4Sc_2O_6Fe_2P_2$. The lattice...
Chen, T. Y., Huang, S. X., Tesanovic, Z., Liu, R. H., Chen, X. H., Chien, C. L.
The superconducting gap in FeAs-based superconductor SmFeAs(O1-xFx) (x = 0.15 and 0.30) and the temperature dependence of the sample with x = 0.15 have been measured by Andreev reflection...
High-field phase-diagram of Fe arsenide superconductors (2009)
Jo, Y. J., Jaroszynski, J., Yamamoto, A., Gurevich, A., Riggs, S. C., Boebinger, G. S., ...
Here, we report an overview of the phase diagram of single layered and double layered Fe arsenide superconductors at high magnetic fields. Our systematic magnetotransport measurements of...
Wang, X. F., Wu, T., Wu, G., Liu, R. H., Chen, H., Xie, Y. L., ...
We study systematically transport, susceptibility and heat capacity for BaFe$_{2-x}$Co$_x$As$_2$ single crystals. In the underdoped region, spin density wave (SDW) transition is observed in both...
Wu, T., Ying, J. J., Wu, G., Liu, R. H., He, Y., Chen, H., ...
The temperature dependence of electron spin resonance (ESR) was studied in the oxypnictide superconductors LaFeAsO$_{1-x}$F$_x$ (x = 0.0 and 0.13). In the samples, the ESR signal indicates that the g...
Liu, R. H., Wu, G., Chen, H., Xie, Y. L., Yan, Y. J., Wu, T., ...
We prepared the samples K$_{1-x}$Ln$_{x}$Fe$_2$As$_2$ (Ln=Sm, Nd and La) with ThCr$_2$Si$_2$-type structure. These samples were characterized by X-ray diffraction, resistivity, susceptibility and...
Baker, P. J., Giblin, S. R., Pratt, F. L., Liu, R. H., Wu, G., Chen, X. H., ...
We report heat capacity measurements of the pnictide materials SmFeAsO$_{1-x}$F$_x$, NdFeAsO, LaFeAsO$_{1-x}$F$_x$ and LiFeAs. For SmFeAsO$_{1-x}$F$_x$, with x close to 0.1, we use 3 He measurements...
Dubroka, Adam, Kim, Kyung Wan, Rössle, Matthias, Malik, V. K., Drew, Alan J., Liu, R. H., ...
We present far-infrared ellipsometric measurements of polycrystalline samples of the pnictide superconductor RFeAsO0.82F0.18 (R=Nd and Sm). We find evidence that the electronic properties are...
Dubroka, Adam, Kim, Kyung Wan, Rössle, Matthias, Malik, V. K., Drew, Alan J., Liu, R. H., ...
We present far-infrared ellipsometric measurements of polycrystalline samples of the pnictide superconductor RFeAsO0.82F0.18 (R=Nd and Sm). We find evidence that the electronic properties are...
Drew, Alan J., Pratt, F. L., Lancaster, T., Blundell, S. J., Baker, P. J., Liu, R. H., ...
Muon spin rotation experiments were performed on the pnictide high temperature superconductor SmFeAsO1-xFx with x=0.18 and 0.3. We observed an unusual enhancement of slow spin fluctuations in the...
Drew, Alan J., Pratt, F. L., Lancaster, T., Blundell, S. J., Baker, P. J., Liu, R. H., ...
Muon spin rotation experiments were performed on the pnictide high temperature superconductor SmFeAsO1-xFx with x=0.18 and 0.3. We observed an unusual enhancement of slow spin fluctuations in the...
Superconductivity at 56 K in Samarium-doped SrFeAsF (2008)
Wu, G., Xie, Y. L., Chen, H., Zhong, M., Liu, R. H., Shi, B. C., ...
We synthesized the samples Sr$_{1-x}$Sm$_x$FFeAs with ZrCuSiAs-type structure. These samples were characterized by resistivity and susceptibility. It is found that substitution of rare earth metal...
A Large Iron Isotope Effect in SmFeAsO1-xFx and Ba1-xKxFe2As2 (2008)
Liu, R. H., Wu, T., Wu, G., Chen, H., Wang, X. F., Xie, Y. L., ...
The recent discovery of superconductivity in oxypnictides with the critical temperature (TC) higher than McMillan limit of 39 K (the theoretical maximum predicted by Bardeen-Cooper-Schrieffer (BCS)...
Balicas, L., Gurevich, A., Jo, Y. J., Jaroszynski, J., Larbalestier, D. C., Liu, R. H., ...
To probe manifestations of multiband superconductivity in oxypnictides, we measured the angular dependence of magnetic torque $\tau(\theta)$ in the mixed state of SmO$_{0.8}$F$_{0.2}$FeAs single...
Doping-Driven Collapse of the SDW Correlation Gap in SmFeAsO$_{1-x}$F$_{x}$ (2008)
Riggs, Scott C., McDonald, R. D., Kemper, J. B., Stegen, Z., Boebinger, G. S., Balakirev, F. F., ...
We report the Hall resistivity, $\rho_{xy}$ of polycrystalline SmFeAsO$_{1-x}$F$_{x}$ for four different fluorine concentrations from the onset of superconductivity through the collapse of the...
Magnetic phase diagram in Eu$_{1-x}$La$_x$Fe$_2$As$_2$ single crystals (2008)
Wu, T., Wu, G., Chen, H., Xie, Y. L., Liu, R. H., Wang, X. F., ...
We have systematically measured resistivity, susceptibility and specific heat under different magnetic fields (H) in Eu$_{1-x}$La$_x$Fe$_2$As$_2$ single crystals. It is found that a metamagnetic...
Drew, A. J., Niedermayer, Ch., Baker, P. J., Pratt, F. L., Blundell, S. J., Lancaster, T., ...
The recent observation of superconductivity with critical temperatures up to 55 K in the FeAs based pnictide compounds marks the first discovery of a non copper-oxide based layered high-Tc...
Coexistence of the spin-density-wave and superconductivity in the (Ba,K)Fe2As2 (2008)
Chen, H., Ren, Y., Qiu, Y., Bao, Wei, Liu, R. H., Wu, G., ...
The relation between the spin-density-wave (SDW) and superconducting order is a central topic in current research on the FeAs-based high Tc superconductors. Conflicting results exist in the...
Wu, G., Chen, H., Wu, T., Xie, Y. L., Yan, Y. J., Liu, R. H., ...
We report that intrinsic transport and magnetic properties, and their anisotropy from high quality single crystal $CaFe_2As_2$. The resistivity anisotropy ($\rho_c/\rho_{ab}$) is $\sim 50 $, and less...
Margadonna, Serena, Takabayashi, Yasuhiro, McDonald, Martin T., Brunelli, Michela, Wu, G., Liu, R. H., ...
The fluorine-doped rare-earth iron oxyarsenides, REFeAsO1-xFx (RE =rare earth) have recently emerged as a new family of high-temperature superconductors with transition temperatures (Tc) as high as...
Riggs, S. C., Kemper, J. B., Jo, Y., Stegen, Z., Balicas, L., Boebinger, G. S., ...
We report the resistivity of a series of fluorine-doped SmFeAsO1-xFx polycrystalline superconductors in magnetic fields up to 60T. For underdoped samples (x < 0.15), the low temperature resistive...
Wang, X. F., Wu, T., Wu, G., Chen, H., Xie, Y. L., Ying, J. J., ...
Sizable single crystals of $BaFe_2As_2$ have been grown with self-flux method. The crystals are plate-like with c-axis perpendicular to the plane. The size can be as large as 3 x 5 x 0.2 $mm^3$. The...
Far-infrared probe of superconductivity in SmO$_{1-x}$F$_{x}$FeAs} (2008)
Mirzaei, S. I., Guritanu, V., Kuzmenko, A. B., Senatore, C., Wu, G., ...
We report far-infrared reflectance measurements on polycrystalline superconducting samples of SmO$_{1-x}$F$_{x}$FeAs ($x$ = 0.12, 0.15 and 0.2). We clearly observe superconductivity induced changes...
Superconductivity induced by oxygen deficiency in Sr-doped LaOFeAs (2008)
Wu, G., Chen, H., Xie, Y. L., Yan, Y. J., Wu, T., Liu, R. H., ...
We synthesized Sr-doped $La_{0.85}Sr_{0.15}OFeAs$ sample with single phase, and systematically studied the effect of oxygen deficiency in the Sr-doped LaOFeAs system. It is found that substitution of...
Wu, G., Liu, R. H., Chen, H., Yan, Y. J., Wu, T., Xie, Y. L., ...
We synthesized the samples $Ba_{1-x}M_xFe_2As_2$ (M=La and K) with $ThCr_2Si_2$-type structure. These samples were systematically characterized by resistivity, thermoelectic power (TEP) and Hall...
Jia, Xiaowen, Liu, Haiyun, Zhang, Wentao, Zhao, Lin, Meng, Jianqiao, Liu, Guodong, ...
High resolution photoemission measurements have been carried out on non-superconducting LaOFeAs parent compound and various superconducting R(O1-xFx)FeAs (R=La, Ce and Pr) compounds. We found that...
Ou, H. W., Zhang, Y., Zhao, J. F., Wei, J., Shen, D. W., Zhou, B., ...
We investigated the temperature dependence of the density-of-states in the iron-based superconductor SmO_1-xF_xFeAs (x=0, 0.12, 0.15, 0.2) with high resolution angle-integrated photoemission...
The BCS-like gap in superconductor SmFeAsO_0.85F_0.15 (2008)
Chen, T. Y., Tesanovic, Z., Liu, R. H., Chen, X. H., Chien, C. L.
Since the discovery of superconductivity in the cuprates two decades ago, it has been firmly established that the CuO_2 plane is consequential for high T_C superconductivity and a host of other very...
Liu, Haiyun, Jia, Xiaowen, Zhang, Wentao, Zhao, Lin, Meng, Jianqiao, Liu, Guodong, ...
High resolution photoemission measurements have been carried out on non-superconducting SmOFeAs parent compound and superconducting Sm(O$_{1-x}$F$_x$)FeAs (x=0.12, and 0.15) compounds. The...
Senatore, C., Cantoni, M., Wu, G., Liu, R. H., Chen, X. H., Flukiger, R.
We report specific heat measurements at magnetic fields up to 20 T on the recently discovered superconductor SmFeAsO$_{0.85}$F$_{0.15}$. The B-T diagram of a polycrystalline...
Dubroka, A., Kim, K. W., Roessle, M., Malik, V. K., Liu, R. H., Wu, G., ...
We present ellipsometric measurements of the far-infrared dielectric response of polycrystalline samples of the new pnictide superconductor RO0.82F0.18FeAs (R=Nd and Sm). We find evidence that the...
Drew, A. J., Pratt, F. L., Lancaster, T., Blundell, S. J., Baker, P. J., Liu, R. H., ...
Muon-spin rotation experiments were performed on the pnictide high temperature superconductor SmFeAsO$_{1-x}$F$_{x}$ with x=0.18 and 0.3. We observed an unusual enhancement of slow spin fluctuations...
Specific heat of the iron-based high-$T_c$ superconductor SmO$_{1-x}$F$_x$FeAs (2008)
Ding, L., He, C., Dong, J. K., Wu, T., Liu, R. H., Chen, X. H., ...
The specific heat $C(T)$ of new iron-based high-$T_c$ superconductor SmO$_{1-x}$F$_x$FeAs ($0 \leq x \leq 0.2$) was systematically studied. For undoped $x$ = 0 sample, a specific heat jump was...
Liu, R. H., Wu, G., Wu, T., Fang, D. F., Chen, H., Li, S. Y., ...
The magnetic fluctuations associated with a quantum critical point (QCP) are widely believed to cause the non-Fermi liquid behaviors and unconventional superconductivities, for example, in heavy...
Lorenz, B., Sasmal, K., Chaudhury, R. P., Chen, X. H., Liu, R. H., Wu, T., ...
High temperature superconductors with a Tc above 40 K have been found to be strongly correlated electron systems and to have a layered structure. Guided by these rules, Kamihara et al. discovered a...
Estimation of the distribution of travel times by repeated simulation (2008)
In recent years, the reliability of transport systems has been widely recognised as a key issue in transport planning and evaluation. To analyse the level of reliability we need information about the...
Superconductivity at 43 K in Samarium-arsenide Oxides $SmFeAsO_{1-x}F_x$ (2008)
Chen, X. H., Wu, T., Wu, G., Liu, R. H., Chen, H., Fang, D. F.
Since the discovery of high-transition temperature ($T_c$) superconductivity in layered copper oxides, extensive efforts have been devoted to explore the higher $T_c$ superconductivity. However, the...
Origin of superconductivity in nominally "undoped" T'-La$_{2-x}$Y$_{x}$CuO$_{4}$ films (2007)
Zhao, L., Liu, R. H., Wu, G., Wang, G. Y., Wu, T., Luo, X. G., ...
We have systematically studied the transport properties of the La$_{2-x}$Y$_{x}$CuO$_{4}$(LYCO) films of T'-phase ($0.05\leq x \leq 0.30$). In this nominally "undoped" system, superconductivity was...
Enantiomeric Analysis of Ephedrines and Norephedrines (2007)
Wang, S. M., Lewis, R. J., Canfield, D., Lia, T. L., Liu, R. H.
Concerned with variations in abuse potential and control status among various isomers of ephedrines and norephedrines, this study was conducted to develop an effective method for the simultaneous...
Zhao, L., Wu, G., Liu, R. H., Chen, X. H.
The superconducting nominal "non-doped" $La_{1.85}Y_{0.15}CuO_4$ (LYCO) thin films are successfully prepared by dc magnetron-sputtering and in situ post-annealing in vacuum. The best $T_{C0}$ more...
Option pricing in a regime-switching model using the fast Fourier transform (2006)
This paper is concerned with fast Fourier transform (FFT) approach to option valuation, where the underlying asset price is governed by a regime-switching geometric Brownian motion. An FFT method for...
Option pricing in a regime-switching model using the fast Fourier transform (2006)
This paper is concerned with fast Fourier transform (FFT) approach to option valuation, where the underlying asset price is governed by a regime-switching geometric Brownian motion. An FFT method for...
Chen, S. A., Liu, R. H., Ting, T. H., Chang, M. S., Chiang, B. N., Kuo, J. S.
1. Effects of intravenous (i.v.) and intravertebral arterial (i.a.) administration of the alpha 2-adrenoceptor agonist, clonidine (Clon) and its antagonist, yohimbine (Yoh, 0.5 mg kg-1, i.v.; 0.05 mg...
NEW NUMERICAL SCHEME FOR PRICING AMERICAN OPTION WITH REGIME-SWITCHING
This paper is concerned with regime-switching American option pricing. We develop new numerical schemes by extending the penalty method approach and by employing the θ-method. With...