1,028 research outputs found
Spectral flow of trimer states of two heavy impurities and one light condensed boson
The spectral flow of three-body (trimer) states consisting of two heavy
(impurity) particles sitting in a condensate of light bosons is considered.
Assuming that the condensate is weakly interaction and that an impurity and a
boson have a zero-range two-body interaction, we use the Born-Oppenheimer
approximation to determine the effective three-body potential. We solve the
resulting Schr\"odinger equation numerically and determine the trimer binding
energies as a function of the coherence length of the light bosonic condensate
particles. The binding energy is found to be suppressed by the presence of the
condensate when the energy scale corresponding to the coherence length becomes
of order the trimer binding energy in the absence of the condensate. We find
that the Efimov scaling property is reflected in the critical values of the
condensate coherence length at which the trimers are pushed into the continuum.Comment: 10 pages including appendices, 4 figures, revised versio
Efimov States of Heavy Impurities in a Bose-Einstein Condensate
We consider the problem of two heavy impurity particles embedded in a gas of
weakly-interacting light mass bosonic particles in the condensed state. Using
the Bogoliubov approach to describe the bosonic gas and the Born-Oppenheimer
approximation for the three-body dynamics, we calculate the modification to the
heavy-heavy two-body potential due to the presence of the condensate. For the
case of resonant interaction between the light bosons and the impurities, we
present (semi)-analytical results for the potential in the limit of a large
condensate coherence length. In particular, we find a formula for the
modification of the Efimov scaling factor due to the presence of a degenerate
bosonic gas background.Comment: 6 pages, 3 figures, final versio
Effective field theory of interactions on the lattice
We consider renormalization of effective field theory interactions by
discretizing the continuum on a tight-binding lattice. After studying the
one-dimensional problem, we address s-wave collisions in three dimensions and
relate the bare lattice coupling constants to the continuum coupling constants.
Our method constitutes a very simple avenue for the systematic renormalization
in effective field theory, and is especially useful as the number of
interaction parameters increases.Comment: 7 pages, 0 figure
Emergence of junction dynamics in a strongly interacting Bose mixture
We study the dynamics of a one-dimensional system composed of a bosonic
background and one impurity in single- and double-well trapping geometries. In
the limit of strong interactions, this system can be modeled by a spin chain
where the exchange coefficients are determined by the geometry of the trap. We
observe non-trivial dynamics when the repulsion between the impurity and the
background is dominant. In this regime, the system exhibits oscillations that
resemble the dynamics of a Josephson junction. Furthermore, the double-well
geometry allows for an enhancement in the tunneling as compared to the
single-well case.Comment: 20 pages, 9 figure
Dynamical realization of magnetic states in a strongly interacting Bose mixture
We describe the dynamical preparation of magnetic states in a strongly
interacting two-component Bose gas in a harmonic trap. By mapping this system
to an effective spin chain model, we obtain the dynamical spin densities and
the fidelities for a few-body system. We show that the spatial profiles transit
between ferromagnetic and antiferromagnetic states as the intraspecies
interaction parameter is slowly increased.Comment: 6 pages, 7 figure
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