Quantum Simulators

Liste des Contributions

2. Magic in many-body systems

Marcello Dalmonte (The Abdus Salam International Centre for Theoretical Physics)

05/02/2024 10:00

Quantum resources have entered the many body state over the last two decades. Apart from the prototypical case of entanglement, relatively little is known about how such resources relate to physical phenomena, a question that is of pivotal importance for the understanding of quantum simulators and computers as many-body systems.

In this talk, I will show how magic - a type of resource that...

3. Passive two-photon dissipation for bit-flip error correction of a cat code

Benjamin Huard (ENS Lyon)

05/02/2024 11:15

Bosonic codes offer a resource-efficient method to quantum error correction [1]. Of particular interest, autonomous correction was successfully demonstrated for cat codes [2–5], where the logical |0⟩ and |1⟩ states are coherent states of opposite amplitudes |α⟩ and | − α⟩ in a superconducting resonator with single-photon loss rates κ1 as low as possible. They correct bit-flip errors by either...

4. Strongly-interacting bosons at dimensional crossover: single-particle correlation and anomalous cooling

Hepeng Yao (University of Geneva)

05/02/2024 12:00

Dimensionality plays an essential role in determining the nature and properties of quantum gases. Fruitful physics may appear at the crossover between dimensions. In the current generation of cold atom experiments, the dimensionality of the system can be controlled by optical lattices. In this talk, I will firstly present our recent study of strongly-interacting bosons at 2D-1D dimensional...

5. Quantum simulation of the boundary sine-Gordon model in superconducting circuits

Serge Florens (Institut Néel)

05/02/2024 14:30

Superconducting junction arrays constitute a versatile and tunable platform to engineer model Hamiltonians that are relevant for quantum many-body systems, dissipative quantummechanics, and non-linear quantum optics. We investigate the detailed AC spectroscopy of the boundary sine-Gordon (BSG) model for a circuit designed with a large impedance value below the resistance quantum. This regime...

6. Magnetism and spin squeezing with arrays of Rydberg atoms

Antoine Browaeys (Institut d’Optique, CNRS)

05/02/2024 15:15

This talk will present our recent work on the use of arrays of Rydberg atoms to study equilibrium and out-of-equilibrium quantum magnetism and to generate entangled states useful for quantum metrology. We rely on laser-cooled ensembles of up to one hundred individual atoms trapped in microscopic optical tweezer arrays. By exciting the atoms into Rydberg states, we make them interact by the...

7. Many-body quantum heat engines based on free-fermion systems.

Davide Rossini (University of Pisa)

05/02/2024 16:30

We study the thermodynamics of free-fermion systems coupled to quantum
thermal baths within a Markovian approximation. In particular, we construct
a four-stroke quantum Otto engine by alternately coupling such kind of
systems to two reservoirs at different temperatures and operating adiabatic
switches of some Hamiltonian parameters, followed by isochoric transformations.

We show that...

8. Exploring quantum criticality in a 4D quantum disordered system

Adam Rançon (Université de Lille)

05/02/2024 17:15

The localization-delocalization transition in disordered media is ubiquitous in quantum and classiacal systems. It is one of the rare transition for which there is no mean-field theory valid in any dimensions. We report the observation and characterization of the Anderson transition in 4D using ultracold atoms as a quantum simulator with synthetic dimensions.

We characterize the universal...

9. Strongly-Correlated Bosons in Optical Quasicrystals: Localization, fractality, and Bose-glass physics

Laurent Sanchez Palencia (Center for Theoretical Physics, CNRS)

06/02/2024 09:15

Quasicrystals, a fascinating class of materials with long-range but nonperiodic order, exhibit fascinating properties due to their unique position at the crossroads of long-range-ordered and disordered systems. These include remarkable localization and fractal properties. While such properties are well known for single particles, the strongly-correlated regime remains largely unexplored....

14. Time-Convolutionless Master Equation Applied to Adiabatic Elimination

Angela Riva (LPENS)

06/02/2024 10:00

In Open Quantum Systems (OQS) theory, where the effective dynamics of a subsystem are described by tracing out environmental degrees of freedom, model reduction techniques become crucial for both conceptual understanding and practical efficiency. In this work, we study the connection between two model reduction methods for systems described by a Lindblad equation. The first is the Time...

11. Kardar Parisi Zhang universal scaling in the coherence of polariton condensates

Jacqueline Bloch (C2N)

06/02/2024 11:15

The Kardar–Parisi–Zhang (KPZ) equation[1], originally derived to describe the kinetic roughening of growing interfaces is a stochastic non-linear differential equation that applies to a large class of non-equilibrium systems, ranging from the growth of nematic liquid crystal clusters, of bacterial colonies, or the propagation of a combustion front. The shape of such an interface h(r,t) is...

12. Bogoliubov excitations driven by thermal lattice phonons in a quantum fluid of light

Irenée Frérot (Institute Néel, CNRS)

06/02/2024 12:00

The elementary excitations in weakly interacting quantum fluids have a non-trivial nature which is at the basis of defining quantum phenomena such as superfluidity. These excitations and the physics they lead to have been explored in closed quantum systems at thermal equilibrium both theoretically within the celebrated Bogoliubov framework, and experimentally in quantum fluids of ultracold...

13. Steering and Quantum Cooling

Yuval Gefen

06/02/2024 14:30

10. Non-equilibrium dynamics of large bosonic quantum many-body systems under the microscope

Monika Aidelsburger (Max-Planck-Institut für Quantenoptik)

06/02/2024 15:15

Quantum gas microscopy (QGM) provides unique access to the properties of quantum many-body system in- and out-of-equilibrium. In this talk, I will report recent work on thermalizationdynamics of hard-core bosons in quasi-1D systems. We make use of site-resolved densitysnapshots in order to monitor the full counting statistics of particle-number fluctuations inoptical ladders, contrasting...

15. Dynamics of multipartite entanglement: from long-range to short-range interactions

Tommaso Roscilde (ENS Lyon)

06/02/2024 16:30

Quantum simulators realize the most controlled forms of quantum matter, in which one can hope to both design and probe many-body quantum coherence and entanglement. Pursuing this program away from equilibrium offers a much richer palette of entangled states than those possible in equilibrium systems; and the possibility to reach these states in a short time, a fundamental advantage for...

16. Limit Shape Transition in Full Counting Statistics

Dimitri Gangardt

06/02/2024 17:15

Full Counting Statistics (FCS) is a way to characterise
non-local correlations in many body systems. We calculate the generating function of FCS of the particle number on amacroscopic interval in a system of free fermions and reveal the existence of 2+\epsilon order phase transition as a function of the rescaled counting parameter. We characterise the transition as a topological change of...

17. Analog of the ETH for integrable systems

Fabian Essler (University of Oxford)

07/02/2024 09:15

The ETH addresses the structure of matrix elements of local operators in energy eigenstates of generic systems. I will discuss what replaces the ETH for integrable systems.

18. Measuring the local rapidity distribution of 1D Bose gases

Jerome Dubail (Université de lorraine)

07/02/2024 10:00

I will present joint work with Léa Dubois, Guillaume Thémèze Florence Nogrette and Isabelle Bouchoule (Institut d’Optique, Palaiseau, France) on the measurement of the local rapidity distribution in 1D Bose gases.
1D bosons with point-like interaction, also known as Lieb-Liniger gas, display peculiar dynamical behavior because they are (nearly) integrable. The rapidities of a 1D Bose gas are...

19. To learn a mocking-black hole

Alioscia Hamma (Università di Napoli Federico II)

07/02/2024 11:15

Complex quantum systems are both hard to simulate and to learn. Generically, they require exponential resources for both. If one were able to learn and then efficiently simulate a complex quantum process, then one would be able to do wonders: for example, to decode the information scrambled by a black hole leaked through Hawking radiation, thus learning its internal structure.

Some complex...

20. Dynamics of an impurity in a trapped one-dimensional Bose gas

Artem Volosniev (ISTA)

07/02/2024 12:00

An impurity in a Bose gas is a topical cold-atom system that allows one to investigate dynamics of quasi-particles in tunable environments. This set-up is often studied theoretically using homogeneous models, which neglect trapping potentials present in experiments. In this talk, I will consider the effect of an external confinement, and also the effect of temperature in quench dynamics using...

36. Molecular Bose-Einstein Condensates

Tin-Lun (Jason) Ho (The Ohio State University)

07/02/2024 14:30

I shall discuss the two newly discovered molecular BEC: those of ground state dipolar molecules of NaCs achieved in January 2024, and those of G-wave Feshbach molecules realized in 2023. I shall discuss their phase coherence different from those of the atomic BECs.

21. Correlation dynamics and lattice modulation spectroscopy of interacting one dimensional systems

Roberta Citro (Universita’ degli Studi di Salerno & Spin-CNR)

07/02/2024 15:15

Quench and lattice modulation are powerful tools for probing low-energy excitations of interacting many-body systems. We present a study of correlation dynamics and absorbed energy power of one-dimensional interacting systems (fermionic and bosonic) subjected either to a quench or to a periodic drive of the optical lattice. For these Tomonaga-Luttinger liquids we find a universal scaling of...

37. Theory of free fermions dynamics under partial post-selected monitoring

Alessandro Romito (Lancaster Unviersity)

07/02/2024 16:30

Monitored quantum systems undergo Measurement-induced Phase Transitions (MiPTs) stemming from the interplay between measurements and unitary dynamics. When the detector readout is post-selected to match a given value, the dynamics is generated by a Non-Hermitian Hamiltonian with MiPTs characterized by different universal features.

Here, we present a partial post-selected stochastic...

22. Resonance Cascades as a Tool of Quantum Number Theory

Maxime Olchanyi (University of Massachusetts Boston)

08/02/2024 09:15

In this presentation, we consider situations where the existence of a contiguous cascade of quantum resonant transitions is predicated on the validity of a particular statement in number theory. As a case study, we look at the following trivial statement: "Any power of 3 is an integer."

Consequently, we "test" this statement in a numerical experiment where we demonstrate an un-impeded...

23. Holographic Realization of the Prime Number Quantum Potential

Andrea Trombettoni (University of Trieste)

08/02/2024 10:00

I plan to start the seminar by presenting a discussion of the experimental realization with holographic techniques of the prime number quantum potential, defined as the potential entering the single-particle Schrödinger Hamiltonian with eigenvalues given by the first N prime numbers. We also implemented the potential having as eigenvalues the first lucky numbers, a sequence of integers...

24. Quasi-one dimensional dipolar bosonic systems: from gas to droplet formation

Stefania De Palo

08/02/2024 11:15

We study a tightly trapped one-dimensional dipolar gas of bosonic atoms for which we derive the equation of state using a variational approximation based on the Lieb-Liniger gas Bethe ansatz wave function. We test our results by computing the breathing mode after solving the stationary generalized Gross-Pitaevskii equation, finding very good agreement with experiments.

When the strength of...

25. Strongly interacting mixtures in 1D box traps: nonequilibrium dynamics and symmetry breaking

Silvia Musolino (Institut de Physique de Nice)

08/02/2024 12:00

My talk focuses on strongly repulsive one-dimensional gases consisting of two-equally balanced spin components under a box confinement. We describe these systems using a generalized Tonks-Girardeau ansatz for the many-body wave function [1, 2].

In particular, we are interested in the nonequilibrium dynamics induced by the initial separation of the spin components and the subsequent...

26. Quantum simulation in the age of color

Sylvain Capponi (Université Paul Sabatier)

08/02/2024 14:30

Alkaline-earth and ytterbium cold atomic gases make it possible to simulate SU(N)-symmetric fermionic systems in a very controlled fashion. Such a high symmetry is expected to give rise to a variety of novel phenomena ranging from molecular Luttinger liquids to (symmetry-protected) topological phases.

I will discuss some of the phases that can be stabilized in a one dimensional lattice,...

27. Asymptotic quantum many-body scars

Leonardo Mazza (Université Paris Saclay)

08/02/2024 15:15

We consider a quantum lattice spin model featuring exact quasiparticle towers of eigenstates with low entanglement at finite size, known as quantum many-body scars (QMBS). We show that the states in the neighboring part of the energy spectrum can be superposed to construct entire families of low-entanglement states whose energy variance decreases asymptotically to zero as the lattice size is...

28. Generalised hydrodynamics for quantum fluids at low-temperature: anomalous transport and quantum ripples

Jacopo De Nardis (CYU)

08/02/2024 16:30

I will show some applications and extensions of the theory of generalised hydrodynamics to quantum systems at low temperature. Taking the paradigmatic model of the Lieb-Liniger for interacting bosons, I will show how non-integrable fluids can display super-diffusive charge fluctuations at low temperature and low coupling, and how to correctly describe non-equilibrium quantum fluctuations...

29. Amorphous quantum magnets in a two-dimensional Rydberg atom array

Joseph Vovrosh (PASQAL)

08/02/2024 17:15

Amorphous solids, characterized by a well-defined short-range order but do not present long range order, constitute an important research topic in condensed matter. While their properties are known to differ from their crystalline counterpart, a microscopic description is still missing.

In this talk, we propose to explore amorphous quantum magnets with a Rydberg quantum simulator. To this...

30. Engineering pseudo-thermal distributions in quantum simulators

Juan José Garcia Ripoli (Institute of Fundamental Physics, CSIC)

09/02/2024 09:15

In this talk I will describe our research on QAOA-like algorithms, in which a quantum simulator is used for brief periods of time, in combination with local drives. We have shown in Ref. [1] that using a quantum simulator for an Ising mode just once, for an arbitrarily brief period of time, results in a pure state that resembles a Boltzmann distribution up to a limiting temperature, that...

31. Quantum simulation of the tricritical Ising model in tunable Josephson junction ladders

Matteo Rizzi (Universität zu Köln)

09/02/2024 10:00

L. Maffi, N. Tausendpfund, M. Rizzi, M. Burrello

Modern hybrid superconductor-semiconductor Josephson junction arrays are a promising platform for analog quantum simulations. Their controllable and non-sinusoidal energy/phase relation opens the path to implement nontrivial interactions and study the emergence of exotic quantum phase transitions. Here, we propose the analysis of an array of...

32. Prediction and Observation of the Universal Hall Response in Strongly Interacting Fermions

Michele Filippone (CEA)

09/02/2024 11:15

The Hall effect originates from the motion of charged particles in a magnetic field and
has deep consequences for the description and characterization of materials, far beyond
the context of condensed matter physics. Understanding the Hall effect in interacting
systems still represents a fundamental challenge.

33. From Středa’s formula to Luttinger’s theorem: Topological signatures unveiled through density probes

Lucila Peralta (Université libre de bruxelles)

09/02/2024 12:00

Identifying experimentally accessible probes that are able to reveal truly distinctive properties of topological phases of matter has remained as an ever-relevant mission. In this talk, I will start reviewing recent advances that were made possible thanks to a remarkable thermodynamic relation known as the Widom-Středa formula, which relates the quantized Hall conductivity of an insulator to...

34. Fermionization of 2D anyons in a tight wave-guide

Nicolas Rougerie (ENS)

09/02/2024 14:30

Since free quantum particles with general statistics parameter α ∈ ]0, 2[ are formally equivalent to free bosons (or fermions) strongly coupled to an appropriate gauge field, it is tempting to simulate exotic statistics e.g. using cold atoms coupled to density-dependent synthetic gauge fields.

This has raised interest both in the context of 2D and 1D anyons, reviving the question of the...

35. A definir by Eugene Demler

09/02/2024 15:15

1. Registration/Opening