Multichannel parametrization of \pi N scattering amplitudes and extraction of resonance parameters

We present results of a new multichannel partial-wave analysis for \pi N scattering in the c.m. energy range 1080 to 2100 MeV. This work explicitly includes \eta N and K \Lambda channels and the single pion photoproduction channel. Resonance parameters were extracted by fitting partial-wave amplitudes from all considered channels using a multichannel parametrization that is consistent with S-matrix unitarity. The resonance parameters so obtained are compared to predictions of quark models

63/65^{63/65}Cu- and 35/37^{35/37}Cl-NMR Studies of Triplet Localization in the Quantum Spin System NH4_4CuCl3_3

$^{63/65}$Cu- and $^{35/37}$Cl-NMR experiments were performed to investigate triplet localization in the $S=1/2$ dimer compound NH$_4$CuCl$_3$, which shows magnetization plateaus at one-quarter and three-quarters of the saturation magnetization. In $^{63/65}$Cu-NMR experiments, signal from only the singlet Cu site was observed, because that from the triplet Cu site was invisible due to the strong spin fluctuation of onsite 3$d$-spins. We found that the temperature dependence of the shift of $^{63/65}$Cu-NMR spectra at the singlet Cu site deviated from that of macroscopic magnetization below T=6 K. This deviation is interpreted as the triplet localization in this system. From the $^{35/37}$Cl-NMR experiments at the 1/4-plateau phase, we found the two different temperature dependences of Cl-shift, namely the temperature dependence of one deviates below T=6 K from that of the macroscopic magnetization as observed in the $^{63/65}$Cu-NMR experiments, whereas the other corresponds well with that of the macroscopic magnetization in the entire experimental temperature region. We interpreted these dependences as reflecting the transferred hyperfine field at the Cl site located at a singlet site and at a triplet site, respectively. This result also indicates that the triplets are localized at low temperatures. $^{63/65}$Cu-NMR experiments performed at high magnetic fields between the one-quarter and three-quarters magnetization plateaus have revealed that the two differently oriented dimers in the unit cell are equally occupied by triplets, the fact of which limits the theoretical model on the periodic structure of the localized triplets.Comment: 19 pages, 9 figures, submitted to PRB (in press

Cu-NMR study on the disordered quantum spin magnet with the Bose-glass ground state

Cu-NMR study has been performed on the disordered spin-gap system Tl1-xKxCuCl3 In the high-field H > HC=\Delta/\mu_B, where \Delta is the spin-gap, the hyperfine field becomes extremely inhomogeneous at low temperatures due to the field-induced magnetic order, indicating that the ordered spin state must be different from the pure TlCuCl3. In the low field H < HC, a saturating behavior in the longitudinal nuclear spin relaxation rate 1/T1 was observed at low temperatures, indicating existence of the magnetic ground state proposed to be Bose-glass phase by Fisher.Comment: RHMF200

On-demand spectrum and space defragmentation in an elastic SDM/FDM/TDM network with mixed multi- and single-core fiber links

We show on-demand multi-wavelength spectrum and space defragmentation in an SDM and elastic network with four programmable nodes and two multi-core fiber links. The combined approach is shown to reduce blocking and hardware requirements in small nodes

Exact Wavefunctions for non-Abelian Chern-Simons Particles

Exact wavefunctions for N non-Abelian Chern-Simons (NACS) particles are obtained by the ladder operator approach. The same method has previously been applied to construct exact wavefunctions for multi-anyon systems. The two distinct base states of the NACS particles that we use are multi-valued and are defined in terms of path ordered line integrals. Only strings of operators that preserve the monodromy properties of these base states are allowed to act on them to generate new states.Comment: 19 pages, CALT-68-187

Demonstration of Adaptive SDN Orchestration:A Real-time Congestion-aware Services Provisioning over OFDM-based 400G OPS and Flexi-WDM OCS

In this Paper, we experimentally demonstrate highly flexible and intelligent interdomain coordinated actions based on adaptive software-defined networking (SDN) orchestration. An advanced multidomain multitechnology testbed is implemented, which consists of a 400-Gb/s variable capacity optical packet switching domain and a Tb/s-class flexi-grid wavelength division multiplexed optical circuit switching domain. The SDN-controllable transponders and the extended transport applications programming interface enable the congestion-aware provisioning of end-to-end real-time services. At the data plane level, different transponders based on orthogonal frequency division multiplexing are employed for inter/intradomain links in order to adaptively provision services with fine granularity. For adaptation, SDN-capable domain-specific optical performance monitors are also introduced. In the control plane, the applications based network operations architecture has been extended and addressed as an adaptive SDN orchestrator

Dimensionality and Irreversibility Field in YBa_2Cu_3O_7 Films (High Field Superconductors)

In order to investigate the relationship between the flux pinning and dimensionality, the critical current density J_c for YBa_2Cu_3O_7 films was measured as a function of temperature, field and tilt angle between field and c-axis. The kink anomaly in the temperature dependence of J_c for B⊥c was observed as the dimensional crossover from 3D extrinsic pinning to 2D intrinsic pinning. The irreversibility field B_i for B//c was measured in fields up to 23T and estimated to be 90T at 30K using the scaling law of the pinning force densities. The enhancement of B_i from a power law (1-T/T_c)^n with n≈1.5 for B//c was observed below 40K. This suggests the formation of the 2-dimensional pancake vortex in YBa_2Cu_3O_7