1,925 research outputs found
Magnetic-field effects on the in-plane electrical resistivity in the single-crystal LaBaCuO and LaNdSrCuO around : Relating to the field-induced stripe order
Temperature dependence of the in-plane electrical resistivity, , in various magnetic fields has been measured in the single-crystal
LaBaCuO with , 0.10, 0.11 and
LaNdSrCuO with . It has been found that the
superconducting transition curve shows a so-called fan-shape broadening in
magnetic fields for , while it shifts toward the low-temperature side
in parallel with increasing field for and 0.12 where the charge-spin
stripe order is formed at low temperatures. As for , the broadening is
observed in low fields and it changes to the parallel shift in high fields
above 9 T. Moreover, the normal-state value of at low
temperatures markedly increases with increasing field up to 15 T. It is
possible that these pronounced features of are understood in terms of
the magnetic-field-induced stabilization of the stripe order suggested from the
neutron-scattering measurements in the La-214 system. The in
the normal state at low temperatures has been found to be proportional to
ln(1/) for , 0.11 and 0.12. The ln(1/) dependence of is robust even in the stripe-ordered state.Comment: 6 pages, 4 figures, ver. 2 has been accepted for publication in Phys.
Rev.
Effect of layer charge on chemical and physical properties of synthetic K-fluorine micas
The original publication is available at www.springerlink.com.ArticleJOURNAL OF MATERIALS SCIENCE. 40(21): 5597-5602 (2005)journal articl
Out-of-plane dielectric constant and insulator-superconductor transition in Bi_2Sr_2Dy_{1-x}Er_xCu_2O_8 single crystals
The out-of-plane dielectric constant of the parent insulator of the
high-temperature superconductor Bi_2Sr_2(Dy,Er)Cu_2O_8 was measured and
analysed from 80 to 300 K in the frequency range of 10^6-10^9 Hz. All the
samples were found to show a fairly large value of 10-60, implying some kind of
charge inhomogeneity in the CuO_2 plane. Considering that the superconducting
sample Bi_2Sr_2(Ca,Pr)Cu_2O_8 also shows a similar dielectric constant, the
charge inhomogeneity plays an important role in the insulator-superconductor
transition.Comment: RevTex4 format, 5 pages, 3 figures, submitted to J. Phys. Condens.
Ma
Low-energy electron scattering by CH_3F, CH_2F_2, CHF_3, and CF_4
We present measured and calculated differential cross sections, as well as calculated integral cross sections, for elastic electron collisions with CH_3F, CH_2F_2, CHF_3, and CF_4. The calculated cross sections were obtained with the Schwinger multichannel method, and a Born-closure procedure was used to improve the differential cross sections for polar systems. Polarization effects were found to be relevant even for systems with moderately large permanent dipole moments, such as CH_3F and CHF_3. In general, there is good agreement between theory and experiment
Reconstructing Bohr's Reply to EPR in Algebraic Quantum Theory
Halvorson and Clifton have given a mathematical reconstruction of Bohr's
reply to Einstein, Podolsky and Rosen (EPR), and argued that this reply is
dictated by the two requirements of classicality and objectivity for the
description of experimental data, by proving consistency between their
objectivity requirement and a contextualized version of the EPR reality
criterion which had been introduced by Howard in his earlier analysis of Bohr's
reply. In the present paper, we generalize the above consistency theorem, with
a rather elementary proof, to a general formulation of EPR states applicable to
both non-relativistic quantum mechanics and algebraic quantum field theory; and
we clarify the elements of reality in EPR states in terms of Bohr's
requirements of classicality and objectivity, in a general formulation of
algebraic quantum theory.Comment: 13 pages, Late
Formation of hydrogen-boron complexes in boron-doped silicon treated with a high concentration of hydrogen atoms
The formation of hydrogen (H) related complexes and their effect on boron (B) dopant were investigated in B-ion implanted and annealed silicon (Si) substrates treated with a high concentration of H. Isotope shifts by replacement of 10B with 11B were observed for some H-related Raman peaks, but not for other peaks. This shows proof of the formation of B-H complexes in which H directly bonds to B in Si. This is an experimental result concerning the formation of B-H complexes with H bonded primarily to B. Electrical resistivity measurements showed that the B acceptors are passivated via the formation of the observed B-H complexes, as well as the well-known passivation center in B-doped Si; namely, the H-B passivation center
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