5,180 research outputs found
LaCo2B2: A Co-based layered superconductor with a ThCr2Si2-type structure
LaCo2B2 with a ThCr2Si2-type structure composed of alternately stacked La and
CoB layers exhibits metallic electrical conductivity and Pauli paramagnetic
behavior down to 2K. Bulk superconductivity with a Tc of ~4K emerges upon
substitution with dopant elements; i.e., isovalent substitution to form
(La1-xYx)Co2B2, or aliovalent substitution to form La(Co1-xFex)2B2. Highly
covalent bonding between Co 3d and B 2p levels in the CoB layers, which is
caused by the B 2p level being shallower than the Fermi level, removes magnetic
ordering from Co 3d electrons even in the undoped samples.Comment: 3 figure
Successful toric intraocular lens implantation in a patient with induced cataract and astigmatism after posterior chamber toric phakic intraocular lens implantation: a case report
<p>Abstract</p> <p>Introduction</p> <p>We report the case of a patient in whom simultaneous toric phakic intraocular lens removal and phacoemulsification with toric intraocular lens implantation were beneficial for reducing pre-existing astigmatism and acquiring good visual outcomes in eyes with implantable collamer lens-induced cataract and astigmatism.</p> <p>Case presentation</p> <p>A 53-year-old woman had undergone toric implantable collamer lens implantation three years earlier. After informed consent was obtained, we performed simultaneous toric implantable collamer lens removal and phacoemulsification with toric intraocular lens implantation. Preoperatively, the manifest refraction was 0, -0.5 × 15, with an uncorrected visual acuity of 0.7 and a best spectacle-corrected visual acuity of 0.8. Postoperatively, the manifest refraction was improved to 0, -0.5 × 180, with an uncorrected visual acuity of 1.2 and a best spectacle-corrected visual acuity of 1.5. No vision-threatening complications were observed.</p> <p>Conclusion</p> <p>Toric intraocular lens implantation may be a good surgical option for the correction of spherical and cylindrical errors in eyes with implantable collamer lens-induced cataract and astigmatism.</p
Reduction of ion thermal diffusivity inside a magnetic island in JT-60U Tokamak plasma
A peaked ion temperature profile is observed inside the magnetic island during mode locking after the back transition from H mode to L mode in JT-60U. The thermal diffusivity evaluated inside the magnetic island is 0.1m2/s, which is much smaller than that outside the magnetic island by an order of magnitude. The present experiment gives clear evidence that ion heat transport inside a magnetic island can bifurcate and the transport level can be suppressed to the very low level associated with the strong flow shear at the boundary
Parallelization of Markov chain generation and its application to the multicanonical method
We develop a simple algorithm to parallelize generation processes of Markov
chains. In this algorithm, multiple Markov chains are generated in parallel and
jointed together to make a longer Markov chain. The joints between the
constituent Markov chains are processed using the detailed balance. We apply
the parallelization algorithm to multicanonical calculations of the
two-dimensional Ising model and demonstrate accurate estimation of
multicanonical weights.Comment: 15 pages, 5 figures, uses elsart.cl
Thin film growth by pulsed laser deposition and properties of 122-type iron-based superconductor AE(Fe1--xCox)2As2 (AE = alkaline earth)
This paper reports comprehensive results on thin-film growth of 122-type
iron-pnictide superconductors, AE(Fe1-xCox)2As2 (AE = Ca, Sr, and Ba,
AEFe2As2:Co) by a pulsed laser deposition method using a neodymium-doped
yttrium aluminum garnet laser as an excitation source. The most critical
parameter to produce the SrFe2As2:Co and BaFe2As2:Co phases is the substrate
temperature (Ts). It is difficult to produce highly-pure CaFe2As2:Co phase thin
film at any Ts. For BaFe2As2:Co epitaxial films, controlling Ts at 800-850
{\deg}C and growth rate to 2.8-3.3 {\AA}/s produced high-quality films with
good crystallinity, flat surfaces, and high critical current densities > 1
MA/cm2, which were obtained for film thicknesses from 100 to 500 nm. The doping
concentration x was optimized for Ba(Fe1-xCox)2As2 epitaxial films, leading to
the highest critical temperature of 25.5 K in the epitaxial films with the
nominal x = 0.075.Comment: will be published in the special issue of Superconductor Science and
Technology, `Iron12
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