Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userCreating superfluid vortex rings in artificial magnetic fields
299
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
Artificial gauge fields are versatile tools that allow to influence the dynamics of ultracold atoms in Bose-Einstein condensates. Here we discuss a method of artificial gauge field generation stemming from the evanescent fields of the curved surface of an optical nanofibre. The exponential decay of the evanescent fields leads to large gradients in the generalized Rabi frequency and therefore to the presence of geometric vector and scalar potentials. By solving the Gross-Pitaevskii equation in the presence of the artificial gauge fields originating from the fundamental HE$_{11}$ mode of the fibre, we show that vortex rings can be created in a controlled manner. We also calculate the magnetic fields resulting from the higher order HE$_{21}$, TE$_{01}$, and TM$_{01}$ modes and compare them to the fundamental HE$_{11}$ mode.
rate research
Read More
In a recent article, Yefsah et al. [Nature 499, 426 (2013)] report the observation of an unusual excitation in an elongated harmonically trapped unitary Fermi gas. After phase imprinting a domain wall, they observe oscillations almost an order of magnitude slower than predicted by any theory of domain walls which they interpret as a heavy soliton of inertial mass some 200 times larger than the free fermion mass or 50 times larger than expected for a domain wall. We present compelling evidence that this soliton is instead a quantized vortex ring by showing that the main aspects of the experiment can be naturally explained within the framework of time-dependent superfluid DFT.
We present a simple Hamiltonian description of the dynamics of a quantized vortex ring in a trapped superfluid, compare this description with dynamical simulations, and characterize the dependence of the dynamics of the shape of the trap.
In a shaken Bose-Einstein condensate, confined in a vibrating trap, there can appear different nonlinear coherent modes. Here we concentrate on two types of such coherent modes, vortex ring solitons and vortex rings. In a cylindrical trap, vortex ring solitons can be characterized as nonlinear Hermite-Laguerre modes, whose description can be done by means of optimized perturbation theory. The energy, required for creating vortex ring solitons, is larger than that needed for forming vortex rings. This is why, at a moderate excitation energy, vortex rings appear before vortex ring solitons. The generation of vortex rings is illustrated by numerical simulations for trapped $^{87}$Rb atoms.
In this letter we show that the vortex lattice structure in the Bose-Fermi superfluid mixture can undergo a sequence of structure transitions when the Fermi superfluid is tuned from the BCS regime to the BEC regime. This is due to different vortex core structure of the Fermi superfluid in the BCS regime and in the BEC regime. In the former the vortex core is nearly filled, while the density at the vortex core gradually decreases until it empties out at the BEC regime. Therefore, with the density-density interaction between the Bose and the Fermi superfluids, the two sets of vortex lattices interact stronger in the BEC regime that yields the structure transition of vortex lattices. In view of recent realization of this superfluid mixture and vortices therein, our theoretical predication can be verified experimentally in near future.
We investigate the ground state properties of ultracold atoms with long range interactions trapped in a two leg ladder configuration in the presence of an artificial magnetic field. Using a Gross-Pitaevskii approach and a mean field Gutzwiller variational method, we explore both the weakly interacting and strongly interacting regime, respectively. We calculate the boundaries between the density-wave/supersolid and the Mott-insulator/superfluid phases as a function of magnetic flux and uncover regions of supersolidity. The mean-field results are confirmed by numerical simulations using a cluster mean field approach.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
