We study the topological properties of interacting and non-interacting bosons loaded in the orbital angular momentum states l = 1 in a lattice of rings with alternating distances [Phys. Rev. A 108, 023317 (2023)]. At the single-particle level, the two circulation states within each site lead to two decoupled Su-Schrieffer-Heeger lattices with correlated topological phases. We characterize the...
By means of a simple non-perturbative numerical approach, we compute the topological phase diagram for ultracold atoms in shaken honeycomb lattices, under the optimal driving discussed by A. Verdeny and F. Mintert [Phys. Rev. A 92, 063615 (2015)]. These results are used to provide a general discussion of different approaches for computing the effective Floquet Hamiltonian of periodically...
Trapped ions can be used to simulate a rich variety of bosonic many-body phases that can be implemented with the vibrational degrees of freedom. We will show that by using parametric couplings, phonons in trapped ions can undergo topological dissipative phase transitions. The latter are the phononic counterparts of topological amplifiers, and can be used for sensing ultraweak forces and...
Different systems with (nearly) dispersion-free energy bands have appeared in the past years, from magic angle twisted bilayer graphene to optical lattices with exotic lattice geometries, such as the Lieb lattice or the Kagome lattice. Flat bands provide a fascinating arena for strongly correlated many-body phenomena, since their physics is automatically dominated by interactions. In the...
Rydberg atoms in arrays of optical tweezers offer new perspectives for applications in quantum simulation, quantum computation, and quantum metrology. In this talk, I will describe our recent efforts to control dipolar interactions between Rydberg states to engineer a 2D XY spin Hamiltonian. In this model, we adiabatically prepare low-temperature states of both the XY ferro- and...
Quantum-gas microscopy is a powerful tool to study individual particle behavior in quantum many-body systems. Realizing those systems with alkaline-earth atoms such as strontium gives rise to exciting phenomena. For example, bosonic strontium in sub-wavelength atomic arrays exhibits strong cooperative effects in atom-photon scattering. The fermionic isotope in the optical lattice enables...
The driven Dicke model, wherein an ensemble of atoms is driven by an external field and undergoes collective spontaneous emission due to coupling to a leaky cavity mode, is a paradigmatic model that exhibits a driven dissipative phase transition as a function of driving power. Recently, a highly analogous phase transition was experimentally observed, not in a cavity setting, but rather in a...
Supersolids are an exotic phase of matter that combines seemingly opposing characteristics of solids and superfluids. They display spontaneous translational symmetry breaking manifesting in crystalline order, while also possessing superfluid properties like frictionless flow. Supersolids were originally predicted over fifty years ago in the context of solid Helium, but were first observed only...
Ultracold bosons in optical lattices provide a fertile platform for studying strongly-correlated many-body systems in a highly controllable manner. Bose-Hubbard (BH) models well describe bosons in optical lattices and have been widely investigated theoretically and experimentally. The conventional BH model consists of the nearest neighbor hopping and on-site interaction between bosons confined...
Supersolids are a phase of matter exhibiting both superfluidity and a periodic density modulation typical of crystals. When formed via quantum phase transition from a superfluid, they require a formation time before their density pattern develops. Some protocols/schemes are proposed for experimental applications, building on earlier descriptions of the role roton instability plays in the...
For open quantum systems, integration of the bath degrees of freedom using the second order cumulant expansion in the Keldysh path integral provides an alternative derivation of the effective action for systems coupled to general baths. The baths can be interacting and not necessarily Markovian. Using this method in the Markovian limit, we compute the particle loss dynamics in various models...
We study the impurity problem with dipolar Fermi atoms in a bilayer geometry. By evaluating the polaron spectrum, we disclose the appearance of a Rydberg-like series of attractive branches when the distance between the layers becomes smaller. We relate them to the appearance of newly bound molecular states by evaluating their orbital angular momentum component. We observe an interchange of...
We present the Dysprosium density functional (Dy-DF), a density functional to describe droplet formation and supersolidity in dipolar systems.
Making use of quantum Monte Carlo we compute with accuracy the equation of state of $^{162}$Dy. The quantum correlation energy contribution is used to modify the usual Lee-Huang-Yang term that accounts for quantum correlations in the widely used...
We explore the thermal effects in the phase diagram of a dipolar BEC confined in a tubular geometry, and show that temperature significantly shifts the low density point where the order of the phase transition between the supersolid and fluid phases changes. We also investigate the effect of a shell-shaped confinement in dipolar physics at zero temperature, and show that it leads to the...
