7 research outputs found
Fault-Tolerant Exact State Transmission
We show that a category of one-dimensional XY-type models may enable
high-fidelity quantum state transmissions, regardless of details of coupling
configurations. This observation leads to a fault- tolerant design of a state
transmission setup. The setup is fault-tolerant, with specified thresholds,
against engineering failures of coupling configurations, fabrication
imperfections or defects, and even time-dependent noises. We propose the
implementation of the fault-tolerant scheme using hard-core bosons in
one-dimensional optical lattices.Comment: 5 pages and 4 figure
Shortcuts to adiabaticity in a time-dependent box
A method is proposed to drive an ultrafast non-adiabatic dynamics of an
ultracold gas trapped in a box potential. The resulting state is free from
spurious excitations associated with the breakdown of adiabaticity, and
preserves the quantum correlations of the initial state up to a scaling factor.
The process relies on the existence of an adiabatic invariant and the inversion
of the dynamical self-similar scaling law dictated by it. Its physical
implementation generally requires the use of an auxiliary expulsive potential
analogous to those used in soliton control. The method is extended to a broad
family of many-body systems. As illustrative examples we consider the ultrafast
expansion of a Tonks-Girardeau gas and of Bose-Einstein condensates in
different dimensions, where the method exhibits an excellent robustness against
different regimes of interactions and the features of an experimentally
realizable box potential.Comment: 6 pp, 4 figures, typo in Eq. (6) fixe