Investigation of novel high T<SUB>c</SUB> superconducting oxides

Our results of microscopic and macroscopic studies of novel high Tc superconductors are discussed. They permit a straightforward comparison of the nature of the superconductivity in 40 K range (La2CuO4 type) and 90 K range (YBa2Cu3O7type) superconductors

Some applications of nuclear orientation

SIGLEAvailable from British Library Document Supply Centre- DSC:D36491/81 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

STATISTICAL TENSORS FOR THE ANALYSIS OF GAMMA-RAY EMISSION FROM A NON-AXIALLY-SYMMETRIC NUCLEAR ENSEMBLE

A tabulation of statistical tensors q (I) for the analysis of -ray emission from a non-axially-symmetric nuclear ensemble H=AIz+P{-12[Iz2-13I(I+1)]+12(I+2+I-2)} has been prepared. The tables cover all values of the magnetic and quadrupole hyperfine parameters A and P, for 1&lt;∼I&lt;∼8. Explicit rotation matrices are also given which enable the tabulated statistical tensors to be transformed into those appropriate to other frames of reference. Special attention is given to off-diagonal tensors q (I), q 0, and it is suggested that statistical-tensor diagrams 22(I) vs 02(I), etc., are a useful way of presenting nuclear-orientation data. © 1979 The American Physical Society

GAMMA-RAY EMISSION FROM SYMMETRIC ORDERED NUCLEAR-SPIN STRUCTURES AT LOW-TEMPERATURES

The temperature dependence of -ray emission patterns from symmetric ordered nuclear-spin systems is discussed with particular reference to planar spin configurations. In particular, explicit expressions for "average statistical tensors" »q(I) are derived, for nuclear-spin structures with two-, three-, four-, and six-fold axes of symmetry. Several interesting identities are derived, which are useful aids in the analysis of a given nuclear orientation experiment. For example, if the nuclear structure possesses either a twofold or an effective twofold axis of symmetry, then the temperature isotherms for 22 vs 02 statistical-tensor diagrams are simply parallel straight lines. © 1979 The American Physical Society

Heat capacity and magnetic susceptibility of mixed valent YbPt<SUB>2</SUB>Si<SUB>2</SUB>

From heat capacity and magnetic susceptibility results, we conclude that YbPt2Si2 is a homogeneously mixed valent compound

Investigation of 4f-magnetism in CeNi<SUB>2</SUB>P<SUB>2</SUB>, EuNi<SUB>2</SUB>P<SUB>2</SUB> and YbNi<SUB>2</SUB>P<SUB>2</SUB> by susceptibility and NMR studies

The results of 31P NMR Knight shift (KS) and spin-lattice relaxation time (T1) as well as magnetic susceptibility (&#958;) measurements in the temperature interval 4.2-300K are reported for the compounds RENi2P2(RE = Ce, EuandYb) in order to understand the nature of the 41 magnetism in these compounds. The KS results conclusively establish that all these compounds exhibit non-magnetic ground states. There is a low-temperature upturn in &#958; for CeNi2P2 and YbNi2P2 presumably due to magnetic impurities. The estimated spin fluctuation temperatures (Tsf) for EuNi2P2 above 50K agree qualitatively with those obtained earlier from M&#246;ssbauer and &#958; data employing ionic interconfigurational fluctuation model, but seem to disagree at low temperatures. Implications of this result are discussed