24,189 research outputs found
Multiparty quantum secret sharing with pure entangled states and decoy photons
We present a scheme for multiparty quantum secret sharing of a private key
with pure entangled states and decoy photons. The boss, say Alice uses the
decoy photons, which are randomly in one of the four nonorthogonal
single-photon states, to prevent a potentially dishonest agent from
eavesdropping freely. This scheme requires the parties of communication to have
neither an ideal single-photon quantum source nor a maximally entangled one,
which makes this scheme more convenient than others in a practical application.
Moreover, it has the advantage of having high intrinsic efficiency for qubits
and exchanging less classical information in principle.Comment: 5 pages, no figure
Graphene-like quaternary compound SiBCN: a new wide direct band gap semiconductor predicted by a first-principles study
Due to the lack of two-dimensional silicon-based semiconductors and the fact
that most of the components and devices are generated on single-crystal silicon
or silicon-based substrates in modern industry, designing two-dimensional
silicon-based semiconductors is highly desired. With the combination of a swarm
structure search method and density functional theory in this work, a
quaternary compound SiBCN with graphene-like structure is found and displays a
wide direct band gap as expected. The band gap is of ~2.63 eV which is just
between ~2.20 and ~3.39 eV of the highlighted semiconductors SiC and GaN.
Notably, the further calculation reveals that SiBCN possesses high carrier
mobility with ~5.14x10^3 and ~13.07x10^3 cm^2V^-1s^-1 for electron and hole,
respectively. Furthermore, the ab initio molecular dynamics simulations also
show that the graphene-like structure of SiBCN can be well kept even at an
extremely high temperature of 2000 K. The present work tells that designing
ulticomponent silicides may be a practicable way to search for new
silicon-based low-dimensional semiconductors which can match well with the
previous Si-based substrates
- …