27,445 research outputs found
On the Cauchy problem for a two-component Degasperis-Procesi system
This paper is concerned with the Cauchy problem for a two-component
Degasperis-Procesi system. Firstly, the local well-posedness for this system in
the nonhomogeneous Besov spaces is established. Then the precise blow-up
scenario for strong solutions to the system is derived. Finally, two new
blow-up criterions and the exact blow-up rate of strong solutions to the system
are presented
Skyrmion dynamics in a chiral magnet driven by periodically varying spin currents
In this work, we investigated the spin dynamics in a slab of chiral magnets
induced by an alternating (ac) spin current. Periodic trajectories of the
skyrmion in real space are discovered under the ac current as a result of the
Magnus and viscous forces, which originate from the Gilbert damping, the spin
transfer torque, and the -nonadiabatic torque effects. The results are
obtained by numerically solving the Landau-Lifshitz-Gilbert equation and can be
explained by the Thiele equation characterizing the skyrmion core motion
Measuring Majorana fermions qubit state and non-Abelian braiding statistics in quenched inhomogeneous spin ladders
We study the Majorana fermions (MFs) in a spin ladder model. We propose and
numerically show that the MFs qubit state can be read out by measuring the
fusion excitation in the quenched inhomogeneous spin ladders. Moreover, we
construct an exactly solvable T-junction spin ladder model, which can be used
to implement braiding operations of MFs. With the braiding processes simulated
numerically as non-equilibrium quench processes, we verify that the MFs in our
spin ladder model obey the non-Abelian braiding statistics. Our scheme not only
provides a promising platform to study the exotic properties of MFs, but also
has broad range of applications in topological quantum computation.Comment: 5+3 pages, 6 figure
Distinct Spin Liquids and their Transitions in Spin-1/2 XXZ Kagome Antiferromagnets
By using the density matrix renormalization group, we study the spin-liquid
phases of spin- XXZ kagome antiferromagnets. We find that the emergence of
spin liquid phase does not depend on the anisotropy of the XXZ interaction. In
particular, the two extreme limits---Ising (strong interaction) and XY
(zero interaction)---host the same spin-liquid phases as the isotropic
Heisenberg model. Both the time-reversal-invariant spin liquid and the chiral
spin liquid with spontaneous time-reversal symmetry breaking are obtained. We
show they evolve continuously into each other by tuning the second- and
third-neighbor interactions. At last, we discuss the possible implication of
our results on the nature of spin liquid in nearest neighbor XXZ kagome
antiferromagnets, including the most studied nearest neighbor spin- kagome
anti-ferromagnetic Heisenberg model
Universal quantum gates between nitrogen-vacancy centers in a levitated nanodiamond
We propose a scheme to realize universal quantum gates between
nitrogen-vacancy (NV) centers in an optically trapped nanodiamond, through
uniform magnetic field induced coupling between the NV centers and the
torsional mode of the levitated nanodiamond. The gates are tolerant to the
thermal noise of the torsional mode. By combining the scheme with dynamical
decoupling technology, it is found that the high fidelity quantum gates are
possible for the present experimental conditions. The proposed scheme is useful
for NV-center-based quantum network and distributed quantum computationComment: 7 pages, 6 figure
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