Quân Trần - Academia.edu (original) (raw)

Papers by Quân Trần

Proceedings of the 9th international conference on Intelligent user interface - IUI '04, 2004

People routinely rely on physical and electronic systems to remind themselves of details regardin... more People routinely rely on physical and electronic systems to remind themselves of details regarding personal and organizational contacts. These systems include rolodexes, directories and contact databases. In order to access details regarding contacts, users must typically shift their attention from tasks they are performing to the contact system itself in order to manually look-up contacts. This paper presents an approach for automatically retrieving contacts based on users' current context. Results are presented to users in a manner that does not disrupt their tasks, but which allows them to access contact details with a single interaction. The approach promotes the discovery of new contacts that users may not have found otherwise and supports serendipity.

Physical Review D, 1984

Duality in semileptonic τ decay. K. Schilcher Institut für Physik, Johannes-Gutenberg Universität... more Duality in semileptonic τ decay. K. Schilcher Institut für Physik, Johannes-Gutenberg Universität, D-6500 Mainz, West Germany. Minh D. Tran Physics Department, Brookhaven National Laboratory, Upton, New York 11973. Received 4 April 1983; revised 24 October 1983 ...

Physical Review B, 2006

A periodic cluster perturbation theory is used to investigate a fermion system. The theory is bas... more A periodic cluster perturbation theory is used to investigate a fermion system. The theory is based on the dynamical cluster approximation with relaxing of self-consistency. Within the periodic cluster perturbation theory the self-energy is approximated by the self-energy of ...

Physical Review B, 2011

We reveal that local interactions in graphene allow novel spin liquids between the semi-metal and... more We reveal that local interactions in graphene allow novel spin liquids between the semi-metal and antiferromagnetic Mott insulating phases, identified with algebraic spin liquid and Z2 spin liquid, respectively. We argue that the algebraic spin liquid can be regarded as the two dimensional realization of one dimensional spin dynamics, where antiferromagnetic correlations show exactly the same power-law dependence as valence bond correlations. Nature of the Z2 spin liquid turns out to be d + id ′ singlet pairing, but time reversal symmetry is preserved, taking d + id ′ in one valley and d − id ′ in the other valley. We propose the quantized thermal valley Hall effect as an essential feature of this gapped spin liquid state. Quantum phase transitions among the semi-metal, algebraic spin liquid, and Z2 spin liquid are shown to be continuous while the transition from the Z2 spin liquid to the antiferromagnetic Mott insulator turns out to be the first order. We emphasize that both algebraic spin liquid and d ± id ′ Z2 spin liquid can be verified by the quantum Monte Carlo simulation, showing the enhanced symmetry in the algebraic spin liquid and the quantized thermal valley Hall effect in the Z2 spin liquid.

Physical Review B, 2008

The Keldysh boundary problem in a nonequilibrium Falicov-Kimball model in infinite dimensions is ... more The Keldysh boundary problem in a nonequilibrium Falicov-Kimball model in infinite dimensions is studied within the truncated and self-consistent perturbation theories, and the dynamical meanfield theory. Within the model the system is started in equilibrium, and later a uniform electric field is turned on. The Kadanoff-Baym-Wagner equations for the nonequilibrium Green functions are derived, and numerically solved. The contributions of initial correlations are studied by monitoring the system evolution. It is found that the initial correlations are essential for establishing full electron correlations of the system and independent on the starting time of preparing the system in equilibrium. By examining the contributions of the initial correlations to the electric current and the double occupation, we find that the contributions are small in relation to the total value of those physical quantities when the interaction is weak, and significantly increase when the interaction is strong. The neglect of initial correlations may cause artifacts in the nonequilibrium properties of the system, especially in the strong interaction case.