Publications associées à Open quantum system

Adaptive variational low-rank dynamics for open quantum systems

We introduce a model-independent method for the efficient simulation of low-entropy systems, whose dynamics can be accurately described with a limited number of states. Our method leverages the time-dependent variational principle to efficiently integrate ...

Amer Physical Soc2024

Dynamical nuclear polarization for dissipation-induced entanglement in NV centers

Mayeul Sylvain Chipaux, Shashwat Kumar, Géraldine Haack, Shishir Khandelwal

We propose a practical implementation of a two-qubit entanglement engine which denotes a scheme to generate quantum correlations through purely dissipative processes. On a diamond platform, the electron spin transitions of two nitrogen-vacancy (NV) centers ...

Amer Physical Soc2023

Quantum dynamics of dissipative Kerr solitons

Vincenzo Savona, Fabrizio Minganti, Riccardo Rota, Kilian Robert Seibold

Dissipative Kerr solitons arising from parametric gain in ring microresonators are usually described within a classical mean-field framework. Here, we develop a quantum-mechanical model of dissipative Kerr solitons in terms of the Lindblad master equation ...

AMER PHYSICAL SOC2022

Arnoldi-Lindblad time evolution: Faster-than-the-clock algorithm for the spectrum of time-independent and Floquet open quantum systems

Fabrizio Minganti

The characterization of open quantum systems is a central and recurring problem for the development of quantum technologies. For time-independent systems, an (often unique) steady state describes the average physics once all the transient processes have fa ...

VEREIN FORDERUNG OPEN ACCESS PUBLIZIERENS QUANTENWISSENSCHAF2022

Revealing higher-order light and matter energy exchanges using quantum trajectories in ultrastrong coupling

Fabrizio Minganti

The dynamics of open quantum systems is often modeled using master equations, which describe the expected outcome of an experiment (i.e., the average over many realizations of the same dynamics). Quantum trajectories, instead, model the outcome of ideal si ...

AMER PHYSICAL SOC2022

Engineering and characterizing nonclassical states of light in quantum optical networks

Kilian Robert Seibold

The exploration of open quantum many-body systems -systems of microscopic size exhibiting quantum coherence and interacting with their surrounding- has emerged as a key research area over the last years. The recent advances in controlling and preserving qu ...

EPFL2022

Creating and controlling exceptional points of non-Hermitian Hamiltonians via homodyne Lindbladian invariance

Fabrizio Minganti

The exceptional points (EPs) of non-Hermitian Hamiltonians (NHHs) are spectral degeneracies associated with coalescing eigenvalues and eigenvectors, which are associated with remarkable dynamical properties. These EPs can be generated experimentally in ope ...

AMER PHYSICAL SOC2022

Theory of Fano effect in cavity quantum electrodynamics

Alexey Lyasota

We propose a Markovian quantum master equation that can describe the Fano effect directly, by assuming a standard cavity quantum electrodynamics system. The framework allows us to generalize the Fano formula, applicable over the weak- and strong-coupling r ...

AMER PHYSICAL SOC2021

A quantum algorithm for the direct estimation of the steady state of open quantum systems

Vincenzo Savona, Nathan Ramusat

Simulating the dynamics and the non-equilibrium steady state of an open quantum system are hard computational tasks on conventional computers. For the simulation of the time evolution, several efficient quantum algorithms have recently been developed. Howe ...

2021

Fluctuation-dissipation relations in the absence of detailed balance: formalism and applications to active matter

Ignacio Pagonabarraga Mora, Sara Dal Cengio

We present a comprehensive study about the relationship between the way detailed balance is broken in non-equilibrium systems and the resulting violations of the fluctuation-dissipation theorem. Starting from stochastic dynamics with both odd and even vari ...

IOP PUBLISHING LTD2021

Quantum Monte Carlo approach to the non-equilibrium steady state of open quantum systems

Alexandra Nagy

Many-body open quantum systems are exposed to an essentially uncontrollable environment that acts as a source of decoherence and dissipation. As the exact treatment of such models is generally unfeasible, it is favourable to formulate an approximate descri ...

EPFL2020

Dissipative time crystal in an asymmetric nonlinear photonic dimer

Vincenzo Savona, Riccardo Rota, Kilian Robert Seibold

We investigate the behavior of two coupled nonlinear photonic cavities, in the presence of inhomogeneous coherent driving and local dissipations. By solving numerically the quantum master equation, either by diagonalizing the Liouvillian superoperator or b ...

AMER PHYSICAL SOC2020

Nuclear Quantum Effects: Fast and Accurate

Venkat Kapil

Atomistic simulations are a bottom up approach that predict properties of materials by modelling the quantum mechanical behaviour of all electrons and nuclei present in a system. These simulations, however, routinely assume nuclei to be classical particles ...

EPFL2020

Variational Quantum Monte Carlo Method with a Neural-Network Ansatz for Open Quantum Systems

Vincenzo Savona, Alexandra Nagy

The possibility to simulate the properties of many-body open quantum systems with a large number of degrees of freedom (d.o.f.) is the premise to the solution of several outstanding problems in quantum science and quantum information. The challenge posed b ...

AMER PHYSICAL SOC2019

Linear Response Theory and Green-Kubo Relations for Active Matter

Ignacio Pagonabarraga Mora, Sara Dal Cengio

We address the question of how interacting active systems in a nonequilibrium steady state respond to an external perturbation. We establish an extended fluctuation-dissipation theorem for active Brownian particles (ABP), which highlights the role played b ...

2019

The Fluctuation Dissipation Theorem as a Diagnosis and Cure for Zero-Point Energy Leakage in Quantum Thermal Bath Simulations

Sara Bonella

Quantum thermal bath (QTB) simulations reproduce statistical nuclear quantum effects via a Langevin equation with a colored random force. Although this approach has proven efficient for a variety of chemical and condensed-matter problems, the QTB, as many ...

2019

Driven-dissipative quantum Monte Carlo method for open quantum systems

Vincenzo Savona, Alexandra Nagy

We develop a real-time full configuration-interaction quantum Monte Carlo approach to model driven-dissipative open quantum systems with Markovian system-bath coupling. The method enables stochastic sampling of the Liouville–von Neumann time evolution of t ...

2018

Emergent transport in a many-body open system driven by interacting quantum baths

Vincenzo Savona, Eduardo Carlo Mascarenhas Moraes, Juris Reisons

We analyze an open many-body system that is strongly coupled at its boundaries to interacting quantum baths. We show that the two-body interactions inside the baths induce emergent phenomena in the spin transport. The system and baths are modeled as indepe ...

Amer Physical Soc2017

Quantum critical probing and simulation of colored quantum noise

Eduardo Carlo Mascarenhas Moraes

We propose a protocol to simulate the evolution of a non-Markovian open quantum system by considering a collisional process with a many-body system, which plays the role of an environment. As a result of our protocol, the environment spatial correlations a ...

Amer Physical Soc2017

Quantum Correlations under Time Reversal and Incomplete Parity Transformations in the Presence of a Constant Magnetic Field

Sara Bonella

We derive the quantum analogues of some recently discovered symmetry relations for time correlation functions in systems subject to a constant magnetic field. The symmetry relations deal with the effect of time reversal and do not requireas in the formulat ...

Mdpi Ag2017