9,467 research outputs found
Changes of Kondo effect in the junction with DIII-class topological and -wave superconductors
We discuss the change of the Kondo effect in the Josephson junction formed by
the indirect coupling between a one-dimensional \emph{DIII}-class topological
and s-wave superconductors via a quantum dot. By performing the
Schrieffer-Wolff transformation, we find that the single-electron occupation in
the quantum dot induces various correlation modes, such as the Kondo and
singlet-triplet correlations between the quantum dot and the -wave
superconductor and the spin exchange correlation between the dot and Majorana
doublet. Moreover, it plays a nontrivial role in modifying the Josephson
effect, leading to the occurrence of anisotropic and high-order Kondo
correlation. In addition, due to the quantum dot in the Kondo regime, extra
spin exchange correlations contribute to the Josephson effect as well.
Nevertheless, if the \emph{DIII}-class topological superconductor degenerates
into \emph{D}-class because of the destruction of time-reversal invariance, all
such terms will disappear completely. We believe that this work shows the
fundamental difference between the \emph{D}- and \emph{DIII}-class topological
superconductors.Comment: 10 pages, 3 figures. Any comment is welcom
The longlived charged massive scalar field in the higher-dimensional Reissner--Nordstr\"{o}m spacetime
The quasinormal resonance frequency of the higher-dimensional
Reissner--Nordstr\"{o}m (RN) black hole due to charged massive scalar field
perturbation is deduced analytically in the eikonal regime. The characteristic
decay timescale of the charged massive scalar perturbation in the background of
the higher-dimensional RN spacetime is then obtained. The result reveals that
longlived charged massive scalar field can exist in higher-dimensional RN
spacetime under a certain condition.Comment: 6 pages, 1 figur
Graph state basis for Pauli Channels
We introduce graph state basis diagonalization to calculate the coherent
information of a quantum code passing through a Pauli channel. The scheme is
5000 times faster than the best known one for some concatenated repetition
codes, providing us a practical constructive way of approaching the quantum
capacity of a Pauli channel. The calculation of the coherent information of
non-additive quantum code can also be greatly simplified in graph state basis.Comment: 5 page
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