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21.
The results of measurements of spin correlations and magnetonuclear cross-correlations (MNCCs) in the system 154Sm1−x
SrxMnO3 with the perovskite structure (x=0.25,0.4) in the low-temperature phase in magnetic fields 0<H<1 kOe are presented. These are the first measurements performed by the small-angle polarized-neutron scattering method (SAPNS).
It is shown that ferromagnetic correlations with a scale of 180–250 Å and MNCCs characterizing the intercoupling of the magnetic
and lattice subsystems on this scale exist in the system. It is found that in the low-temperature phase the system exhibits
spin-glass properties.
Pis’ma Zh. éksp. Teor. Fiz. 69, No. 4, 323–328 (25 February 1999) 相似文献
22.
S. V. Grigoriev V. V. Piyadov A. I. Okorokov H. Eckerlebe 《Physics of the Solid State》2010,52(5):948-951
The critical small-angle scattering of polarized neutrons from spin fluctuations in a nickel single crystal with a special inclined geometry of the magnetic field has been studied. The method of inclined geometry makes it possible to investigate not only two-particle spin correlations but also three-particle spin correlations that determine the polarization-dependent contribution to scattering, which is asymmetric with respect to the momentum transfer q. This contribution depends on the momentum transfer q as 1/(q 2 + ξ?2)5/2, where f is the neutron scattering correlation length; it linearly increases with an increase in the magnetic field H in the low-field range and then reaches saturation. The results obtained are in good agreement with the similarity theory. 相似文献
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24.
To detect scattering by magnetic correlations and to estimate their characteristic space scale, YBa2(Cu1?x Fex)3O7+y ceramic with x=0.13 and y=0.4 is investigated by the small-angle scattering of polarized neutrons. The measurements are carried out in the range of temperatures 15 K?T?315 K and magnetic fields 0<H?4500 Oe. Anomalies in the temperature curves of the intensity I(T,q) (where q is the momentum transfer) and the polarization P(T,q) are observed in the temperature range T<40 K. Interference between nuclear and magnetic scattering is also observed in this temperature range. The observed phenomena are interpreted as scattering by magnetic correlations having a scale 70 Å<R<370 Å. Irreversible effects and the type of magnetic ordering are discussed. 相似文献
25.
Experimental results obtained by studying soft hadron jets in pion-proton and pion-nucleus reactions at intermediate energies with the aid of traditional collective variables are presented. Analytic approximations that describe, at a qualitative level, the dependences of collective parameters on the energy and multiplicity are proposed. Estimates obtained for strong coupling constant by studying collective variables are in reasonable agreement with its world-average value and with the results extracted by using different methods. The behavior of traditional collective variables as functions of the multiplicity in various interactions makes it possible to obtain a universal estimate for the lower boundary of the region of experimental manifestations of jets in multiparticle-production processes. 相似文献
26.
V.V. Okorokov D.L. Tolchenkov I.S. Khizhnyakov Yu.N. Cheblukov Yu.Ya. Lapitsky G.A. Iferov Yu.N. Zhukova 《Physics letters. A》1973,43(6):485-487
Experimental results concerning to discovery of coherent Coulomb excitation for the He+ ions passing through monocrystalline silver film are reported. 相似文献