We obtain analytic solutions to the Gross-Pitaevskii equation with negative scattering length in highly asymmetric traps. find that these traps Bose--Einstein condensates behave like quasiparticles and do not expand when trapping one direction is eliminated. The results can be applicable control of motion condensates.

We solve the time-dependent Gross-Pitaevskii equation by a variational ansatz to calculate excitation spectrum of Bose-Einstein condensate in trap. The trial wave function is Gaussian which allows an essentially analytical treatment problem. Our results reproduce numerical calculations over whole range from small large particle numbers, and agree exactly with Stringari strong interaction limit. Excellent agreement obtained recent JILA experiment predictions for negative scattering length...

A variational technique is applied to solve the time-dependent nonlinear Schr\"odinger equation (Gross-Pitaevskii equation) with goal model dynamics of dilute ultracold atom clouds in Bose-Einstein condensed phase. We derive analytical predictions for collapse, equilibrium widths, and evolution laws condensate parameters find them be very good agreement our numerical simulations equation. It found that not only number particles, but also both initial width effect different perturbations may...

We analyze the structure of first azimuthal stationary state for a nonlinear medium presenting simultaneously cubic (focusing) and quintic (defocusing) dependence with light intensity in refractive index. This solution takes form dark vortex hosted compact beam. The existence these modes is guaranteed if flux exceeds certain minimum threshold are extremely stable fluxes larger than critical value that we calculated. verified robust nature this inducing internal oscillations by an initial...

We study a four-level atomic system with electromagnetically induced transparency giant chi(3) and chi(5) susceptibilities of opposite signs. This will allow us to obtain multidimensional solitons light condensates surface tension properties analogous those usual liquids.

An optical vortex is a screw dislocation in light field that carries quantized orbital angular momentum and, due to cancellations of the twisting along propagation axis, experiences zero intensity at its center. When viewed perpendicular plane appears as dark region center surrounded by bright concentric ring light. We give detailed instructions for generating vortices and structures computer-generated holograms describe various methods manipulating resulting structures.

We demonstrate, through numerical simulations, the controllable emission of matter-wave bursts from a Bose-Einstein condensate in shallow optical dipole trap. The process is triggered by spatial variations scattering length along trapping axis. In our approach, outcoupling mechanisms are atom-atom interactions and thus, trap remains unaltered. Once emitted, matter wave forms robust soliton. calculate analytically parameters for experimental implementation these solitons.

Metal Halide Perovskites (MHPs) have arisen as promising materials to construct cost-effective photovoltaic and light emission devices. The study of nonlinear optical properties MHPs is necessary get similar success in photonic devices, which practically absent the literature. determination third order coefficients typically done by Z-scan technique, limited scattering polycrystalline thin films. In this work, we studied CH3NH3PbX3 (MAPbX3) films colloidal CsPbX3 nanoparticles with three...

In this work, a real-time collision avoidance algorithm was presented for autonomous navigation in the presence of fixed and moving obstacles building environments. The current implementation is designed between waypoints predefined flight trajectory that would be performed by an UAV during tasks such as inspections or construction progress monitoring. It uses simplified geometry generated from point cloud scenario. addition, it also employs information 3D sensors to detect position people...

We show that a laser beam can be diffracted by more concentrated light pulse due to quantum vacuum effects. compute analytically the intensity pattern in realistic experimental configuration, and discuss how it used measure for first time parameters describing photon-photon scattering vacuum. In particular, we Quantum Electrodynamics prediction detected single-shot experiment at future 100 petawatt lasers such as ELI or HIPER. On other hand, if carried out one of present high power...

In this letter we introduce the concept of stabilized vector solitons as nonlinear waves constructed by addition mutually incoherent Townes that are under effect a periodic modulation nonlinearity. We analyze stability new kind structures and describe their behavior formation in Manakov-like interactions. Potential applications our results Bose-Einstein condensation optics also discussed.

We show that a laser beam which propagates through cubic-quintic nonlinear optical material may reach, for given power, condensed state with collisional dynamics resembling liquid drop. qualitatively describe the analogies between this system and usual fluids them by simulating numerically total reflections of these beams planar boundaries localized defects. use analogy ``liquid light'' to stress connections quantum fluids, including Bose-Einstein condensates.

In this paper we analyze atom lasers based on the spatial modulation of scattering length a Bose-Einstein condensate. We demonstrate, through numerical simulations and approximate analytical methods, controllable emission matter-wave bursts study dependence process shape along axis emission. also role an additional in time.

In a recent paper, we have shown that the QED nonlinear corrections imply phase correction to linear evolution of crossing electromagnetic waves in vacuum. Here, provide more complete analysis, including full numerical solution wave equations for short-distance propagation symmetric configuration. The excellent agreement such with result obtain using our perturbatively motivated variational approach is then used justify an analytical approximation can be applied general case. This allows us...

We discuss the dynamics of interacting dark-bright two-dimensional vector solitons in multicomponent immiscible bulk Bose-Einstein condensates. describe matter-wave molecules without a scalar counterpart that can be seen as bound states objects. also analyze possibility using these structures building blocks for design switchers.

We have investigated the dynamics of optical beams in a cubic (focusing)–quintic (defocusing) nonlinear medium. In particular, we found that strong can show long-lived elliptical oscillations, whereas other cases, i.e., for weak or cylindrical decay quickly. This finding explains observed higher efficiency fusion two beams. also investigated, numerically and analytically, robustness to an initial phase chirp.

We study the cubic- (focusing-)quintic (defocusing) nonlinear Schrödinger equation in two transverse dimensions. discuss a family of stationary traveling waves, including rarefaction pulses and vortex-antivortex pairs, background critical amplitude. show that these can be generated inside flattop soliton when smaller bright collides with it. The fate evolution strongly depends on relative phase solitons. Among several possibilities, we find dark pulse reemerge as soliton.

We analyze theoretically the Schr\"odinger-Poisson equation in two transverse dimensions presence of a Kerr term. The model describes nonlinear propagation optical beams thermo-optical media and can be regarded as an analog system for self-gravitating self-interacting wave. compute numerically family radially symmetric ground-state bright stationary solutions focusing defocusing local nonlinearity, keeping both cases nonlocal nonlinearity. also excited states oscillations induced by fixing...

By performing numerical simulations, we discuss the collisional dynamics of stable solitary waves in Schrodinger-Poisson equation. In framework a model which part or all dark matter is Bose-Einstein condensate ultralight axions, show that these can naturally account for relative displacement between and ordinary galactic cluster Abell 3827, whose recent observation first empirical evidence interactions beyond gravity. The essential assumption existence solitonic cores kiloparsec scale. For...

We demonstrate, through numerical simulations, the generation of stable vortex lattices in light condensates. This can be achieved by propagating several concentric laser beams with nested vortices different topological charges an optical material a cubic-quintic nonlinearity. have considered initial conditions, and all cases net resulting lattice is equal to charge outer vortex. The exhibits rotation similar motion superfluids. These arrays could used implement all-optical photonic crystal...

We show that QED nonlinear effects imply a phase correction to the linear evolution of electromagnetic waves in vacuum. provide explicit solutions modified Maxwell's equations for propagation superposition two plane waves, and calculate analytically numerically corresponding shift. This provides new framework search all-optical signatures photon-photon scattering In particular, we propose an experiment measuring shift projected high-power laser facilities.

We investigate the existence of self-trapped nonlinear waves with multiple phase singularities. Working cubic-quintic Schrödinger equation, we focus on configurations an antivortex surrounded by a triangular arrangement vortices within hosting soliton. find stationary patterns that can be interpreted as stable vortex crystals, constituting first example configuration this sort space-independent potentials. Their stability is linked to their norm, transitioning from unstable size increases,...