S. P. Kruglov

Magnetism in disordered magnetic Fe82−xNixCr18

The zero field μSR-method has been used to study the magnetism in the disordered magnetic alloy Fe82−xNixCr18 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.

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.

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−>TN′ where TN 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.

The MSR-investigation of antiferromagnetic phase transitions in erbium

The muon spin relaxation rateΛ (T) in an orientated polycrystalline sample of erbium constructed of large monocrystals has been measured for temperatures 20 <T<300 K. It has been shown that theΛ (T) for erbium is bounded from above asT → TN, whereTN=84.4 K is the Néel temperature. This fact may be explained by assuming that atT=TN erbium undergoes a weak phase-transition of the first order.

μSR study of Cu10Zr7

It is shown that temperature dependences Λ(T) of dipole relaxation rate of the positive muon spin in crystalline and amorphous states of Cu10Zr7 are approximately the same over the temperature interval 20–300 K. this fact points out approximately identical close-order structure of crystalline and amorphous states of Cu10Zr7 alloy.

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.

The depolarization of muons in solid hydrogen

The relaxation rate (ξ) of the spin of positive muons has been measured in hydrogen containing 2%; 55% and 66% O−H2 in the temperature range 1.5 to 20 K in a transverse magnetic field of 286 gauss.

μSR study of the superconducting state Nb3Al

By means of the uSR method, the critical temperature Tk=(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.

Positive muon diffusion in helicoidally-ordered antiferromagnets

A method for measuring the time scale for positive muon diffusion in helicoidally ordered antiferromagnets is proposed. The experiment shows that the muon diffusion in dusprosium over the temperature interval 100–175 K is a tunneling process.

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.