Publications associées à Décohérence quantique

Probing structural and dynamic properties of MAPbCl3 hybrid perovskite using Mn2+ EPR

Hybrid methylammonium (MA) lead halide perovskites have emerged as materials exhibiting excellent photovoltaic performance related to their rich structural and dynamic properties. Here, we use multifrequency (X-, Q-, and W-band) electron paramagnetic reson ...

Royal Soc Chemistry2024

Mechanically induced correlated errors on superconducting qubits with relaxation times exceeding 0.4 ms

Tobias Kippenberg, Amir Youssefi, Marco Scigliuzzo, Mahdi Chegnizadeh, Shingo Kono, Xuxin Wang

Superconducting qubits are among the most advanced candidates for achieving fault-tolerant quantum computing. Despite recent significant advancements in the qubit lifetimes, the origin of the loss mechanism for state-of-the-art qubits is still subject to i ...

Nature Portfolio2024

Quantum Error Correction and Simulation in Open Bosonic Systems

David Schlegel

Quantum computers have the potential to surpass conventional computing, but they are hindered by noise which induces errors that ultimately lead to the loss of quantum information. This necessitates the development of quantum error correction strategies fo ...

EPFL2024

How to Find Molecules with Long-lasting Charge Migration?

Jiri Vanicek, Alan Scheidegger, Nikolay Golubev

Under certain conditions, the ionization of a molecule may create a superposition of electronic states, leading to ultrafast electron dynamics. If controlled, this motion could be used in attochemistry applications, but it has been shown that the decoheren ...

SWISS CHEMICAL SOC2023

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

A squeezed mechanical oscillator with millisecond quantum decoherence

Tobias Kippenberg, Amir Youssefi, Mahdi Chegnizadeh, Shingo Kono

An enduring challenge in constructing mechanical-oscillator-based hybrid quantum systems is to ensure engineered coupling to an auxiliary degree of freedom and maintain good mechanical isolation from the environment, that is, low quantum decoherence, consi ...

NATURE PORTFOLIO2023

Self-correcting quantum many-body control using reinforcement learning with tensor networks

Friederike Metz

Quantum many-body control is a central milestone en route to harnessing quantum technologies. However, the exponential growth of the Hilbert space dimension with the number of qubits makes it challenging to classically simulate quantum many-body systems an ...

NATURE PORTFOLIO2023

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

Symmetry in design and decoding of polar-like codes

Kirill Ivanov

The beginning of 21st century provided us with many answers about how to reach the channel capacity. Polarization and spatial coupling are two techniques for achieving the capacity of binary memoryless symmetric channels under low-complexity decoding algor ...

EPFL2022

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

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

Quantum coherent microwave-optical transduction using high-overtone bulk acoustic resonances

Tobias Kippenberg

A device capable of converting single quanta of the microwave field to the optical domain is an outstanding endeavor in the context of quantum interconnects between distant superconducting qubits, but likewise can have applications in other fields, such as ...

AMER PHYSICAL SOC2021

Classical variational simulation of the Quantum Approximate Optimization Algorithm

Giuseppe Carleo

A key open question in quantum computing is whether quantum algorithms can potentially offer a significant advantage over classical algorithms for tasks of practical interest. Understanding the limits of classical computing in simulating quantum systems is ...

2021

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

Enumerating Optimal Quantum Circuits using Spectral Classification

Giovanni De Micheli, Mathias Soeken, Giulia Meuli

This work targets fault-tolerant quantum computing and focuses on the problem of mapping reversible circuits into the Clifford+T quantum gate library. We present an automatically-generated database containing minimal-cost quantum circuits for Boolean funct ...

IEEE2020

Mechanical resonators with high dissipation dilution in precision and quantum measurements

Sergey Fedorov

Position measurements of mechanical oscillators underpin experiments spanning from applied nanoscale sensing to endeavors aiming to resolve open fundamental problems of modern physics. Sufficiently precise position measurements are also used for engineerin ...

EPFL2021

Change of beam distribution due to decoherence in the presence of transverse feedback

Xavier Buffat, Sondre Vik Furuseth

The effect of Landau damping is often calculated based on a Gaussian beam distribution in all degrees of freedom. The stability of the beam is however strongly dependent on the details of the distribution. The present study focuses on the change of bunch d ...

IOP PUBLISHING LTD2019

Ultra-coherent nano-mechanical resonators for quantum optomechanics at room temperature

Amir Hossein Ghadimi

Mechanical oscillators are among the most important scientific tools in the modern physics. From the pioneering experiments in 18th by founding fathers of modern physics such as Newton, Hooke and Cavendish to the ground braking experiments in the 21th cent ...

EPFL2018

Excitonic Emission of Monolayer Semiconductors Near-Field Coupled to High-Q Microresonators

Tobias Kippenberg, Clément Christian Javerzac-Galy, Ryan Daniel Schilling, Sina Khorasani, Nicolas Piro Mastracchio, Anshuman Kumar

We present quantum yield measurements of single layer WSe2 (1L-WSe2) integrated with high-Q (Q > 106) optical microdisk cavities, using an efficient (η > 90%) near-field coupling scheme based on a tapered optical fiber. Coupling of the excitonic emission i ...

American Chemical Society (ACS)2018

Dissipation as a resource in circuit quantum electromechanics

László Dániel Tóth

A primary challenge in quantum science and technology is to isolate the fragile quantum states from their environment in order to prevent the irreversible leakage of energy and information which causes decoherence. In the late 1990s, however, a new paradig ...

EPFL2018