Significance Nonequilibrium phenomena in quantum many-body systems are not well understood to date. This applies particular for open systems, coupled an external bath. We use a Bose–Einstein condensate high-finesse optical resonator with ultralow bandwidth emulate the Dicke model. In well-controlled sweeps across Hepp–Lieb–Dicke phase transition, we observe hysteretic dynamics showing power-law scaling respect transition time, which suggests interpretation terms of Kibble–Zurek mechanism....

We present the first experimental realization of a time crystal stabilized by dissipation. The central signature in our implementation driven open atom-cavity system is period doubled switching between distinct checkerboard density wave patterns, induced interplay controlled cavity dissipation, cavity-mediated interactions, and external driving. demonstrate robustness this dynamical phase against parameter changes temporal perturbations driving.Received 21 January 2021Revised 12 April...

We employ a quantum Liouville equation with relaxation to model the recently observed anomalous Hall effect in graphene irradiated by an ultrafast pulse of circularly polarized light. In weak-field regime, we demonstrate that originates from asymmetric population photocarriers Dirac bands. By contrast, strong-field system is driven into non-equilibrium steady state well-described topologically non-trivial Floquet-Bloch Here, current combination imbalance these dressed bands together smaller...

Time crystals are classified as discrete or continuous depending on whether they spontaneously break time translation symmetry. While have been extensively studied in periodically driven systems since their recent discovery, the experimental realization of a crystal is still pending. Here, we report observation limit cycle phase continuously pumped dissipative atom-cavity system, which characterized by emergent oscillations intracavity photon number. We observe that this oscillation random...

We propose an experimental realization of a time crystal using atomic Bose-Einstein condensate in high finesse optical cavity pumped with laser light detuned to the blue side relevant resonance. By mapping out dynamical phase diagram, we identify regions parameter space showing stable limit cycle dynamics. Since model describing system is independent, emergence indicates breaking continuous translation symmetry. Employing semiclassical analysis demonstrate robustness cycles against...

We use bosonization approach to investigate quantum phases in mixtures of bosonic and fermionic atoms confined one dimensional optical lattices. The phase diagrams can be well understood terms polarons, which correspond that are "dressed" by screening clouds the other atom species. For a mixture single species we find charge density wave phase, with fermion pairing, regime separation. two obtain spin phases, Wigner crystal singlet triplet paired states fermions, separation regime....

We map out the critical velocity in crossover from Bose-Einstein condensation to Bardeen-Cooper-Schrieffer superfluidity with ultracold ^{6}Li gases. A small attractive potential is dragged along lines of constant column density. The rate induced heating increases steeply above a v_{c}. In same samples, we measure speed sound v_{s} by exciting density waves and compare results measured values perform numerical simulations regime find very good agreement, validating approach. strongly...

We demonstrate the emergence of a time crystal atoms in high-finesse optical cavity driven by phase-modulated transverse pump field, resulting shaken lattice. This system exhibits macroscopic oscillations number photons and order parameters at noninteger multiples driving period, which signals appearance an incommensurate crystal. The subharmonic oscillatory motion corresponds to dynamical switching between symmetry-broken states, are nonequilibrium bond ordered density wave states....

We demonstrate how the properties of light-induced electronic Floquet states in solids impact natural physical observables, such as transport properties, by capturing environmental influence on electrons. include environment dissipative processes, inter-band decay and dephasing, often ignored predictions. These processes determine band occupations emergent steady state, balancing out optical driving force. In order to benchmark illustrate our framework for physics a realistic solid, we...

We propose a general mechanism for generating limit cycle (LC) oscillations by coupling linear bosonic mode to dissipative nonlinear mode. By analyzing the stability matrix, we show that LCs arise due supercritical Hopf bifurcation. find existence of is independent sign effective interaction. The model can be realized in three-level systems interacting with quantized light as atom-cavity systems. Using such platform, experimentally observe an system attractive optical pump lattice, thereby...

We study the quantum phases of mixtures ultracold bosonic atoms held in an optical lattice that confines motion or hopping to one spatial dimension. The are found by using Tomonaga-Luttinger liquid theory as well numerical method time-evolving block decimation (TEBD). consider a binary mixture equal density with repulsive intraspecies interactions and either attractive interspecies interaction. For homogeneous system, we find paired counterflow superfluid at different filling energies. also...

We study the dynamics of relative phase a bilayer two-dimensional superfluids after two have been decoupled. find that on short time scales shows "light cone" like and creates metastable superfluid state, which can be supercritical. also demonstrate similar light cone for transverse field Ising model. On longer supercritical state relaxes to disordered due dynamical vortex unbinding. This scenario dynamically suppressed proliferation constitutes reverse-Kibble-Zurek effect. this effect both...

Motivated by recent pump-probe experiments indicating enhanced coherent c-axis transport in underdoped YBCO, we study Josephson junctions periodically driven optical pulses. We propose a mechanism for this observation demonstrating that parametrically junction shows an imaginary part of the low-frequency conductivity when driving frequency is above plasma frequency, implying effectively coupling. generalize analysis to bilayer system modeling YBCO. Again, coupling pump blue detuned either...

Unconventional superconductivity in the cuprates emerges from, or coexists with, other types of electronic order. However, these orders are sometimes invisible because their symmetry. For example, possible existence superfluid charge stripes normal state single layer cannot be validated with infrared optics, interlayer tunneling fluctuations vanish on average. Similarly, it is not easy to establish if responsible for dynamical decoupling superconducting layers over broad ranges doping and...

A periodically driven open three-level Dicke model is realized by resonantly shaking the pump field in an atom-cavity system. As unambiguous signature, we demonstrate emergence of a dynamical phase, which atoms localize between antinodes lattice, associated with oscillating net momentum along axis. We observe this phase through periodic switching relative and cavity fields at small fraction driving frequency, suggesting that it exhibits time crystalline character.

While the recently realized dissipative time crystal in a laser-pumped atom-cavity system experiment of Ke{\ss}ler et al. [Phys. Rev. Lett. 127, 043602 (2021)] is qualitatively consistent with theoretical description an idealized limit, here, we investigate stability this presence inhomogeneous potential provided by harmonic trap, and competing short- infinite-range interactions. We note that these features are ubiquitous any realization systems. By mapping out dynamical phase diagram...

Quantum machine learning has emerged as a promising utilization of near-term quantum computation devices. However, algorithmic classes such variational algorithms have been shown to suffer from barren plateaus due vanishing gradients in their parameters spaces. We present an approach algorithm optimization that is based on trainable Fourier coefficients Hamiltonian system parameters. Our ansatz exclusive the extension discrete analog optimal control schemes and nonlocal time. demonstrate...

The breaking of time-reversal symmetry via the spontaneous formation chiral order is ubiquitous in nature. Here, we present an unambiguous demonstration this phenomenon for atoms Bose-Einstein condensed second Bloch band optical lattice. As a key tool, use matter-wave interference technique, which lets us directly observe phase properties superfluid parameter and allows to reconstruct spatial geometry certain low-energy excitations, associated with domains different chirality. Our work marks...

Using a numerical implementation of the truncated Wigner approximation, we simulate experiment reported by Ramanathan et al. in Phys. Rev. Lett. 106, 130401 (2011), which Bose-Einstein condensate is created toroidal trap and set into rotation via phase imprinting technique. A potential barrier then placed to study decay superflow. We find that current decays thermally activated slips, can also be visualized as vortices crossing region radial direction. Adopting notion critical velocity used...

We investigate the superfluid behavior of a Bose-Einstein condensate $^{6}\mathrm{Li}$ molecules. In experiment by Weimer et al. [Phys. Rev. Lett. 114, 095301 (2015)] is stirred weak, red-detuned laser beam along circular path around trap center. The rate induced heating increases steeply above velocity ${v}_{c}$, which we define as critical velocity. Below this velocity, moving creates almost no heating. paper, demonstrate quantitative understanding Using both numerical and analytical...

We study binary mixtures of ultracold atoms, confined to one dimension in an optical lattice, with commensurate densities. Within a Luttinger liquid description, which treats various on equal footing, we derive system renormalization group equations at second order, from determine the rich phase diagrams these mixtures. These phases include charge and spin density wave orders, singlet triplet pairings, polaron pairing [L. Mathey et al., Phys. Rev. Lett. 93, 120404 (2004)], supersolid phase....

The recent experimental realization of dipolar Fermi gases near or below quantum degeneracy provides an opportunity to engineer Hubbard-like models with long-range interactions. Motivated by these experiments, we chart out the theoretical phase diagram interacting fermions on square lattice at zero temperature and half filling. We show that, in addition p-wave superfluid charge density wave order, two new exotic types bond order emerge generically fermion systems. These phases feature...