Cluster Extended Dynamical Mean Field Approach and Unconventional Superconductivity

The extended dynamical mean field theory has played an important role in the study of quantum phase transitions in heavy fermion systems. In order to incorporate the physics of unconventional superconductivity, we develop a cluster version of the extended dynamical mean field theory. In this approach, we show how magnetic order and superconductivity develop as a result of inter-site spin exchange interactions, and analyze in some detail the form of correlation functions. We also discuss the methods that can be used to solve the dynamical equations associated with this approach. Finally, we consider different settings in which our approach can be applied, including the periodic Anderson model for heavy fermion systems.Comment: 15 pages, 2 figures, Replaced with published versio

A Critical Examination to the Unitarized ππ\pi\pi Scattering Chiral Amplitudes

We discuss the Pad\'e approximation to the $\pi\pi$ scattering amplitudes in 1--loop chiral perturbation theory. The approximation restores unitarity and can reproduce the correct resonance poles, but the approximation violates crossing symmetry and produce spurious poles on the complex $s$ plane and therefore plagues its predictions on physical quantities at quantitative level. However we find that one virtual state in the IJ=20 channel may have physical relevance.Comment: 13 pages + 4 eps figures submit to Commun. Theor. Phy

Perbedaan Persepsi Mahasiswa Senior dan Junior Mengenai Profesi Akuntan pada Program S1 di Universitas Katolik Widya Mandala Surabaya

Accounting profession is work that has to be done in a professional and great responsibility towards the public,so that every student who will pursue this work should have the right attitudes and perceptions of the accounting profession. Therefore, when students still in the university they need to be taught to has a positive perception of accounting profession. This research used comparative with hypothesis testing aims to provide empirical evidence on differences in perceptions between senior and junior students of the accounting profession. The samples consist of senior students who have passed all internal and external courses (class of 2007 and 2008) and junior students who have passed the semester 1 (class of 2009 and 2010). The numbers of samples used by proportionate random sampling are 72 samples from senior students and 102 samples from junior students. The tool used is questionaire that contain list of statements. The results showed that there was no difference in perception between senior and junior students of the accounting profession in the bachelor of accounting at Widya Mandala Catholic University Surabaya

Trace element concentration in mango (Mangifera indica L.), seedless guava (Psidium guajava L.) and papaya (Carica papaya L.) grown on agricultural and ex-mining lands of Bidor, Perak

Fruits namely mango, papaya, and seedless guava grown on agricultural and ex-mining lands in Bidor were sampled for analyse of heavy metal contamination. The concentration of mercury (Hg), lead (Pb), copper (Cu), zinc (Zn), nickel (Ni), arsenic (As) and cadmium (Cd) in the fruits were analysed. The results showed that, with the exception of Hg in mango and Pb in guava, fruits grown on agricultural land have higher levels of heavy metals than those grown on ex-mining land. The concentration of heavy metal in all fruits of both soil types ranged from 0.06 to 0.55 mg kgI for Cd, 0.02 to 0.78 mg kgI for Hg, 0.63 to 8.71 mg kgI for Pb, 5.20 to 12.22 mg kgI for Zn, and 2.01 to 5.74 mg kgI for Cu. Both Cr and Ni were not detected in papaya grown on mine spoils, whilst As was not detected in all fruits grown on both types of soils. The findings indicate that all fruits contained unacceptably high levels of Hg and Pb. The probable causes of contamination are discussed. Further studies are required to investigate the cause of heavy metal contamination in these fruits

Highly Efficient Midinfrared On-Chip Electrical Generation of Graphene Plasmons by Inelastic Electron Tunneling Excitation

Inelastic electron tunneling provides a low-energy pathway for the excitation of surface plasmons and light emission. We theoretically investigate tunnel junctions based on metals and graphene. We show that graphene is potentially a highly efficient material for tunneling excitation of plasmons because of its narrow plasmon linewidths, strong emission, and large tunability in the midinfrared wavelength regime. Compared to gold and silver, the enhancement can be up to 10 times for similar wavelengths and up to 5 orders at their respective plasmon operating wavelengths. Tunneling excitation of graphene plasmons promises an efficient technology for on-chip electrical generation and manipulation of plasmons for graphene-based optoelectronics and nanophotonic integrated circuits.Comment: 12 pages, 7 figure