609 research outputs found
Vortex structures of rotating spin-orbit coupled Bose-Einstein condensates
We consider the quasi-2D two-component Bose-Einstein condensates with Rashba
spin-orbit (SO) coupling in a rotating trap. An external Zeeman term favoring
spin polarization along the radial direction is also considered, which has the
same form as the non-canonical part of the mechanical angular momentum. The
rotating condensate exhibits rich structures as varying the strengths of
trapping potential and interaction. With a strong trapping potential, the
condensate exhibits a half-quantum vortex-lattice configuration. Such a
configuration is driven to the normal one by introducing the external radial
Zeeman field. In the case of a weak trap potential, the condensate exhibits a
multi-domain pattern of plane-wave states under the external radial Zeeman
field.Comment: 8 pages, 7 figures, two figures are adde
Imprinting a complete information about a quantum channel on its output state
We introduce a novel property of bipartite quantum states, which we call
"faithfulness", and we say that a state is faithful when acting with a channel
on one of the two quantum systems, the output state carries a complete
information about the channel. The concept of faithfulness can also be extended
to sets of states, when the output states patched together carry a complete
imprinting of the channel.Comment: revtex4, 4 pages, submitted to PR
Complex and real unconventional Bose-Einstein condensations in high orbital bands
We perform the theoretical study on the unconventional Bose-Einstein
condensations (UBEC) in the high bands of optical lattices observed by
Hemmerich's group. These exotic states are characterized by complex-valued
condensate wavefunctions with nodal points, or real-valued ones with nodal
lines, thus are beyond the {\it "no-node"} paradigm of the conventional BECs. A
quantum phase transition is driven by the competition between the single
particle band and interaction energies. The complex UBECs spontaneously break
time-reversal symmetry, exhibiting a vortex-antivortex lattice structure.Comment: 4.2 page
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