13,454 research outputs found
Ultradilute low-dimensional liquids
We calculate the energy of one- and two-dimensional weakly interacting
Bose-Bose mixtures analytically in the Bogoliubov approximation and by using
the diffusion Monte Carlo technique. We show that in the case of attractive
inter- and repulsive intraspecies interactions the energy per particle has a
minimum at a finite density corresponding to a liquid state. We derive the
Gross-Pitaevskii equation to describe droplets of such liquids and solve it
analytically in the one-dimensional case.Comment: published version + supplemental materia
Elliptic fibrations associated with the Einstein spacetimes
Given a conformally nonflat Einstein spacetime we define a fibration over
it. The fibres of this fibration are elliptic curves (2-dimensional tori) or
their degenerate counterparts. Their topology depends on the algebraic type of
the Weyl tensor of the Einstein metric. The fibration is a double branched
cover of the bundle of null direction over the spacetime and is equipped with
six linearly independent 1-forms which satisfy certain relatively simple system
of equations.Comment: 15 pages, Late
Dynamically Generated Open and Hidden Charm Meson Systems
We will study open and hidden charm scalar meson resonances within two
different models. The first one is a direct application of a chiral Lagrangian
already used to study flavor symmetry breaking in Skyrme models. In another
approach to the problem a SU(4) symmetric Lagrangian is built and the symmetry
is broken down to SU(3) by identifying currents where heavy mesons are
exchanged and suppressing those. Unitarization in couple channels leads to
dynamical generation of resonances in both models, in particular a new hidden
charm resonance with mass 3.7 GeV is predicted. The small differences between
these models and with previous works will be discussed.Comment: 32 pages, 10 figures. Added extra calculations with explicit symmetry
breaking terms in chiral Lagrangian
Crystalline phase of strongly interacting Fermi mixtures
We show that the system of weakly bound molecules of heavy and light
fermionic atoms is characterized by a long-range intermolecular repulsion and
can undergo a gas-crystal quantum transition if the mass ratio exceeds a
critical value. For the critical mass ratio above 100 obtained in our
calculations, this crystalline order can be observed as a superlattice in an
optical lattice for heavy atoms with a small filling factor. We also find that
this novel system is sufficiently stable with respect to molecular relaxation
into deep bound states and to the process of trimer formation.Comment: 4 pages, 1 color figure, published versio
Two atoms in an anisotropic harmonic trap
We consider the system of two interacting atoms confined in axially symmetric
harmonic trap. Within the pseudopotential approximation, we solve the
Schroedinger equation exactly, discussing the limits of quasi-one and
quasi-two-dimensional geometries. Finally, we discuss the application of an
energy-dependent pseudopotential, which allows to extend the validity of our
results to the case of tight traps and large scattering lengths.Comment: RevTeX 4 pages, 2 figure
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