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Cergy-Pontoise, France

Cergy-Pontoise University is a French university, in the Academy of Versailles.Cergy-Pontoise University is a public university and a leading centre of teaching and research, which welcomes 17,700 students and 1,500 international students interested in studying abroad.The university is located in the west of Paris , in the Val-d'Oise department.The university offers all levels of graduate and post-graduate studies. 144 bachelors, masters and doctorate degrees are available in a wide range of fields : law, economy and management, languages, literature and social science, and science and technology. Wikipedia.

Trambly De Laissardiere G.,Cergy-Pontoise University | Mayou D.,CNRS Neel Institute
Physical Review Letters | Year: 2013

We propose a unified description of transport in graphene with adsorbates that fully takes into account localization effects and loss of electronic coherence due to inelastic processes. We focus in particular on the role of the scattering properties of the adsorbates and analyze in detail cases with resonant or nonresonant scattering. For both models, we identify several regimes of conduction, depending on the value of the Fermi energy. Sufficiently far from the Dirac energy and at sufficiently small concentrations, the semiclassical theory can be a good approximation. Near the Dirac energy, we identify different quantum regimes, where the conductivity presents universal behaviors. © 2013 American Physical Society. Source

Matzkin A.,Cergy-Pontoise University
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2011

We investigate entanglement for a composite closed system endowed with a scaling property which allows the dynamics to be kept invariant while the effective Planck constant eff of the system is varied. Entanglement increases as eff→0. Moreover, for sufficiently low eff the evolution of the quantum correlations, encapsulated, for example, in the quantum discord, can be obtained from the mutual information of the corresponding classical system. We show this behavior is due to the local suppression of path interferences in the interaction that generates the entanglement. © 2011 American Physical Society. Source

Matzkin A.,Cergy-Pontoise University
Physical Review Letters | Year: 2012

We propose a scheme allowing us to observe the evolution of a quantum system in the semiclassical regime along the paths generated by the propagator. The scheme relies on performing consecutive weak measurements of the position. We show how "weak trajectories" can be extracted from the pointers of a series of devices having weakly interacted with the system. The properties of these weak trajectories are investigated and illustrated in the case of a time-dependent model system. © 2012 American Physical Society. Source

Belliard S.,Cergy-Pontoise University
Nuclear Physics B | Year: 2015

The modified algebraic Bethe ansatz, introduced by Crampé and the author [8], is used to characterize the spectral problem of the Heisenberg XXZ spin-1/2 chain on the segment with lower and upper triangular boundaries. The eigenvalues and the eigenvectors are conjectured. They are characterized by a set of Bethe roots with cardinality equal to N the length of the chain and which satisfies a set of Bethe equations with an additional term. The conjecture follows from exact results for small chains. We also present a factorized formula for the Bethe vectors of the Heisenberg XXZ spin-1/2 chain on the segment with two upper triangular boundaries. © 2015 The Author. Source

De Trambly Laissardiere G.,Cergy-Pontoise University | Mayou D.,CNRS Neel Institute | Magaud L.,CNRS Neel Institute
Nano Letters | Year: 2010

For Dirac electrons the Klein paradox implies that the confinement is difficult to achieve with an electrostatic potential although it can be of great importance for graphene-based devices. Here, ab initio and tight-binding approaches are combined and show that the wave function of Dirac electrons can be localized in rotated graphene bilayers due to the Moire pattern. This localization of wave function is maximum in the limit of the small rotation angle between the two layers. © 2010 American Chemical Society. Source

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