Magnetism in disordered magnetic Fe82−xNixCr18

The zero field μSR-method has been used to study the magnetism in the disordered magnetic alloy Fe_82−xNi_xCr₁₈ near the three-critical, pointx=25. The dynamic and static local field distributions are analyzed. The difference between spin-glass states obtained either from the paramagnetic or after the double transition is discussed.     

μSR study of vortex structure mobility and penetration depth in Bi2Sr2CaCu2O2-δ textured sample

The giant mobility of the magnetic flux in FrFC and ZFC conditions have been studied in textured sample Bi₂Sr₂CaCu₂O_2- bySR. The comparison of results obtained in both cases showed that it is difficult to explain this phenomenon by only thermally activated flux creep and the melting of vortex lattice must be considered. The magnetic field dependence of the melting temperature was obtained for H<90mT. It is shown that the possibility of vortex motion does not affect the results of FC-measurements.     

The effect of radiation defects in silicon single crystal lattice on the characteristic states of the interstitial muonium atom

Radiation defects are shown experimentally to affect differently the normal and anomalous muonium states in silicon. This evidences essentially different mobilities of the two muonium states in the sample lattice.     

Quantum diffusion of muons in bismuth

A muon spin relaxation rate in a super-pure sample of bismuth has been measured. The experimental data and the theory of coherent diffusion in crystalline lattices with shifted levels are compared.     

Anomalously strong relaxation of the polarization of muons in the magnetically ordered and paramagnetic states of the TbMnO<Subscript>3</Subscript> multiferroic

An anomalously strong relaxation of the muon polarization in a magnetically ordered state in the TbMnO₃ multiferroic has been revealed by the method below the μSR Néel temperature (42 K). Such a relaxation is due to the muon channel of relaxation of the polarization and the interaction of the magnetic moment of the muon with inhomogeneities of the internal magnetic field of an ordered state in the form of a cycloid. Above the Néel temperature, beginning with temperatures depending on the applied magnetic field, a two-phase state has been revealed where one phase has an anomalously strong relaxation of the muon polarization for a paramagnetic state. These features of the paramagnetic state are due to short-range magnetic order domains that appear in strongly frustrated TbMnO₃. A true paramagnetic state has been observed only at T ≥ 150 K.     

μSR study of antiferromagnetic phase-transitions in dysprosium and holmium

It is shown that the temperature dependence Λ (T) of the muon spin relaxation rate in the paramagnetic state of dysprosium and holmium does not reveal any singularity at T−>T_N′ where T_N is the Neel temperature. This result contradicts the assumption of the second-order antiferromagnetic phase-transition in these metals and is in good agreement with computations within the renormalization group method.     

μSR study of the superconducting state Nb3Al

By means of the uSR method, the critical temperature T_k=(17.41 0.05) K and the inhomogenety of the internal magnetic field in Nb₃Al in the mixed state for two values of external magnetic fields H=62 Oe and H=285 Oe over the temperature range 9–17 K were measured.     

Observation of a Gabay–Toulouse line in Fe0.6Mn0.4Pt3 alloy

It was shown that in the frustrated ferromagnet belonging to the group of structurally ordered Fe_x Mn_1-x Pt₃ alloys the temperature of the transition from the ferromagnetic state to the asperomagnetic state followed a Gabay–Toulouse line. This revised version was published online in July 2006 with corrections to the Cover Date.     

Investigation of magnetic ordered state in YBa2Cu3O6+x (0.06<X<0.32) bY μSR

The magnetic state properties have been studied in YBa₂Cu₃O_6+x with (0.06SR-studies two precession signals with the frequencies close to 4MHz was observed at T=20÷80K. Possible reasons of the phenomena at T<100K are discussed.     

Temperature dependence of the quadruple interaction and the diffusion of muonium atoms in α-quartz

The results of an experimental investigation of the quadrupole interaction of muonium atom in-quartz in the temperature region 75–300 K are presented. It is show that the observed temperature dependence of the quadrupole interaction parameters is fully determined by the diffusion of muonium.