Professeur UCBN

Groupe : Théorie et phénoménologie

Tél : +33 2 31 45 25 41

PUBLICATIONS

### [in2p3-01498659] Phaseless quantum Monte-Carlo approach to strongly correlated superconductors with stochastic Hartree–Fock–Bogoliubov wavefunctions

30 mars 2017

The so-called phaseless quantum Monte-Carlo method currently offers one of the best performing theoretical framework to investigate interacting Fermi systems. It allows to extract an approximate ground-state wavefunction by averaging independent-particle states undergoing a Brownian motion in (...)

### [in2p3-01334165] Constrained-path quantum Monte Carlo approach for non-yrast states within the shell model

20 juin 2016

The present paper intends to present an extension of the constrained-path quantum Monte Carlo approach allowing to reconstruct non-yrast states in order to reach the complete spectroscopy of nuclei within the interacting shell model. As in the yrast case studied in a previous work, the (...)

### [in2p3-01226192] Intertwined orders from symmetry projected wavefunctions of repulsively interacting Fermi gases in optical lattices

10 novembre 2015

Unconventional strongly correlated phases of the repulsive Fermi-Hubbard model, which could be emulated by ultracold vapors loaded in optical lattices, are investigated by means of energy minimizations with quantum number projection before variation and without any assumed order parameter. In a (...)

### [hal-00000847] Exact pairing correlations in one-dimensionally trapped fermions with stochastic mean-field wave-functions

1er juillet 2015

The canonical thermodynamic properties of a one-dimensional system of interacting spin-1/2 fermions with an attractive zero-range pseudo-potential are investigated within an exact approach. The density operator is evaluated as the statistical average of dyadics formed from a stochastic (...)

### [hal-00628137] Boundary conditions for star matter and other periodic fermionic systems

1er juillet 2015

Bulk fermionic matter, as it can be notably found in supernova matter and neutrons stars, is subject to correlations of infinite range due to the antisymmetrisation of the N-body wave function, which cannot be explicitly accounted for in a practical simulation. This problem is usually addressed (...)

### [in2p3-01109338] Exact ground state of strongly correlated electron systems from symmetry-entangled wave-functions

1er juillet 2015

The four-site Hubbard model is considered from the exact diagonalisation and variational method points of view. It is shown that the exact ground-state can be recovered by a symmetry projected Slater determinant, irrespective of the interaction strength. This is in contrast to the Gutzwiller (...)

### [hal-00090944] Sign-free stochastic mean-field approach to strongly correlated phases of ultracold fermions.

1er juillet 2015

We propose a new projector quantum Monte-Carlo method to investigate the ground state of ultracold fermionic atoms modeled by a lattice Hamiltonian with on-site interaction. The many-body state is reconstructed from Slater determinants that randomly evolve in imaginary-time according to a (...)

### A phase-free quantum Monte Carlo method for the nuclear shell model

26 juillet 2013

The shell model provides a powerful framework for nuclear structure calculations. The nucleons beyond an inert magic core are confined in a valence shell and interact through an effective two-body potential generally determined from the G-matrix method. However, the applicability of the shell (...)

### [in2p3-00805495] A Constrained-Path Quantum Monte-Carlo Approach for the Nuclear Shell Model

17 avril 2013

A new Quantum Monte-Carlo (QMC) approach is proposed to investigate low-lying states of nuclei within the shell model. The formalism relies on a variational symmetry-restored wave-function to guide the underlying Brownian motion. Sign/phase problems that usually plague QMC fermionic simulations (...)

### [in2p3-00805497] Exotic spin, charge and pairing correlations of the two-dimensional doped Hubbard model: a symmetry entangled mean-field approach

4 avril 2013

Intertwining of spin, charge and pairing correlations in the repulsive two-dimensional Hubbard model is shown through unrestricted variational calculations, with projected wavefunctions free of symmetry breaking. A crossover from incommensurate antiferromagnetism to stripe order naturally (...)

### Boundary conditions for star matter and other periodic fermionic systems

3 octobre 2011

Bulk fermionic matter, as it can be notably found in supernova matter and neutrons stars, is subject to correlations of infinite range due to the antisymmetrisation of the N-body wave function, which cannot be explicitly accounted for in a practical simulation. This problem is usually addressed (...)

### Boundary conditions for star matter and other periodic fermionic systems

3 octobre 2011

Bulk fermionic matter, as it can be notably found in supernova matter and neutrons stars, is subject to correlations of infinite range due to the antisymmetrisation of the N-body wave function, which cannot be explicitly accounted for in a practical simulation. This problem is usually addressed (...)

### Sign-free stochastic mean-field approach to strongly correlated phases of ultracold fermions.

30 mai 2007

We propose a new projector quantum Monte-Carlo method to investigate the ground state of ultracold fermionic atoms modeled by a lattice Hamiltonian with on-site interaction. The many-body state is reconstructed from Slater determinants that randomly evolve in imaginary-time according to a (...)

### Sign-free stochastic mean-field approach to strongly correlated phases of ultracold fermions.

30 mai 2007

We propose a new projector quantum Monte-Carlo method to investigate the ground state of ultracold fermionic atoms modeled by a lattice Hamiltonian with on-site interaction. The many-body state is reconstructed from Slater determinants that randomly evolve in imaginary-time according to a (...)

### [in2p3-00019817] Exact stochastic mean-field approach to the Fermionic many-body problem

5 juillet 2006

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### Information theory of open fragmenting systems

8 décembre 2005

An information theory description of finite systems explicitly evolving in time is presented. We impose a MaxEnt variational principle on the Shannon entropy at a given time while the constraints are set at a former time. The resulting density matrix contains explicit time odd components in the (...)

### Information theory of open fragmenting systems

8 décembre 2005

An information theory description of finite systems explicitly evolving in time is presented. We impose a MaxEnt variational principle on the Shannon entropy at a given time while the constraints are set at a former time. The resulting density matrix contains explicit time odd components in the (...)

### Generalized Gibbs ensembles for time dependent processes

17 décembre 2004

An information theory description of finite systems explicitly evolving in time is presented for classical as well as quantum mechanics. We impose a variational principle on the Shannon entropy at a given time while the constraints are set at a former time. The resulting density matrix deviates (...)

### [in2p3-00023474] Generalized Gibbs ensembles for time dependent processes

17 décembre 2004

An information theory description of finite systems explicitly evolving in time is presented for classical as well as quantum mechanics. We impose a variational principle on the Shannon entropy at a given time while the constraints are set at a former time. The resulting density matrix deviates (...)

### Exact pairing correlations in one-dimensionally trapped fermions with stochastic mean-field wave-functions

15 mars 2004

The canonical thermodynamic properties of a one-dimensional system of interacting spin-1/2 fermions with an attractive zero-range pseudo-potential are investigated within an exact approach. The density operator is evaluated as the statistical average of dyadics formed from a stochastic (...)

### Exact pairing correlations in one-dimensionally trapped fermions with stochastic mean-field wave-functions

15 mars 2004

The canonical thermodynamic properties of a one-dimensional system of interacting spin-1/2 fermions with an attractive zero-range pseudo-potential are investigated within an exact approach. The density operator is evaluated as the statistical average of dyadics formed from a stochastic (...)