35,218 research outputs found
Octet baryon masses in next-to-next-to-next-to-leading order covariant baryon chiral perturbation theory
We study the ground-state octet baryon masses and sigma terms using the
covariant baryon chiral perturbation theory (ChPT) with the
extended-on-mass-shell (EOMS) renormalization scheme up to
next-to-next-to-next-to-leading order (NLO). By adjusting the available 19
low-energy constants (LECs), a reasonable fit of the lattice quantum
chromodynamics (LQCD) results from the PACS-CS, LHPC, HSC, QCDSF-UKQCD and
NPLQCD collaborations is achieved. Finite-volume corrections to the lattice
data are calculated self-consistently. Our study shows that NLO BChPT
describes better the light quark mass evolution of the lattice data than the
NNLO BChPT does and the various lattice simulations seem to be consistent with
each other. We also predict the pion and strangeness sigma terms of the octet
baryons using the LECs determined in the fit of their masses. The predicted
pion- and strangeness-nucleon sigma terms are MeV and
MeV, respectively.Comment: 28 pages, 6 figures, minor revisions, typos corrected, version to
appear in JHE
Ultrafast initialization and QND-readout of a spin qubit via control of nanodot-vacuum coupling
Ultrafast initialization enables fault-tolerant processing of quantum
information while QND readout enables scalable quantum computation. By
spatially assembling photon resonators and wave-guides around an n-doped
nanodot and by temporally designing optical pump pulses, an efficient quantum
pathway can be established from an electron spin to a charged exciton to a
cavity photon and finally to a flying photon in the waveguide. Such control of
vacuum-nanodot coupling can be exploited for ultrafast initialization and QND
readout of the spin, which are particularly compatible with the optically
driven spin quantum computers.Comment: 4 pages 3 figure
Recommended from our members
Geochemistry and petrogenesis of volcanic rocks from Daimao Seamount (South China Sea) and their tectonic implications
The South China Sea (SCS) experienced three episodes of seafloor spreading and left three fossil spreading centers presently located at 18°N, 17°N and 15.5°N. Spreading ceased at these three locations during magnetic anomaly 10, 8, and 5c, respectively. Daimao Seamount (16.6. Ma) was formed 10. my after the cessation of the 17°N spreading center. Volcaniclastic rocks and shallow-water carbonate facies near the summit of Daimao Seamount provide key information on the seamount's geologic history. New major and trace element and Sr-Nd-Pb isotopic compositions of basaltic breccia clasts in the volcaniclastics suggest that Daimao and other SCS seamounts have typical ocean island basalt-like composition and possess a 'Dupal' isotopic signature. Our new analyses, combined with available data, indicate that the basaltic foundation of Daimao Seamount was formed through subaqueous explosive volcanic eruptions at 16.6. Ma. The seamount subsided rapidly (>. 0.12. mm/y) at first, allowing the deposition of shallow-water, coral-bearing carbonates around its summit and, then, at a slower rate (<. 0.12. mm/y). We propose that the parental magmas of SCS seamount lavas originated from the Hainan mantle plume. In contrast, lavas from contemporaneous seamounts in other marginal basins in the western Pacific are subduction-related
Theory of control of spin/photon interface for quantum networks
A cavity coupling a charged nanodot and a fiber can act as a quantum
interface, through which a stationary spin qubit and a flying photon qubit can
be inter-converted via cavity-assisted Raman process. This Raman process can be
controlled to generate or annihilate an arbitrarily shaped single-photon
wavepacket by pulse-shaping the controlling laser field. This quantum interface
forms the basis for many essential functions of a quantum network, including
sending, receiving, transferring, swapping, and entangling qubits at
distributed quantum nodes as well as a deterministic source and an efficient
detector of a single photon wavepacket with arbitrarily specified shape and
average photon number. Numerical study of noise effects on the operations shows
high fidelity.Comment: 4 pages, 2 figure
Electromagnetically controlled multiferroic thermal diode
We propose an electromagnetically tunable thermal diode based on a two phase
multiferroics composite. Analytical and full numerical calculations for
prototypical heterojunction composed of Iron on Barium titanate in the
tetragonal phase demonstrate a strong heat rectification effect that can be
controlled externally by a moderate electric field. This finding is of an
importance for thermally based information processing and sensing and can also
be integrated in (spin)electronic circuits for heat management and recycling.Comment: Accepted in Phys. Rev.
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