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1.
T. N. Mamedov V. N. Duginov A. V. Stoykov I. L. Chaplygin D. Herlach U. Zimmermann V. N. Gorelkin J. Major M. Schefzik 《JETP Letters》1998,68(1):64-70
The residual polarization of negative muons in crystal silicon samples with phosphorus (P: 1.6×1013 cm−3) and antimony (Sb: 2×1018 cm−3) impurities is investigated. The measurements are made in a 1000 G magnetic field oriented in a direction transverse to the
muon spin in the temperature range 4–300 K. The relaxation rate and shift of the precession frequency in the silicon sample
with the phosphorus impurity are measured more accurately than previously. It is found that in antimony-doped silicon the
acceptor center
μ
A1 at temperatures below 30 K can be in both ionized and neutral states. The experimental data are interpreted on the basis
of spin-lattice relaxation of the magnetic moment of an acceptor center, formation of acceptor-donor pairs, and recombination
of charge carriers at the acceptor. Preliminary measurements showed a nonzero residual polarization of negative muons in germanium.
Pis’ma Zh. éksp. Teor. Fiz. 68, No. 1, 61–66 (10 July 1998) 相似文献
2.
S. G. Barsov A. L. Getalov S. L. Ginsburg V. P. Koptev S. P. Kruglov L. A. Kuzmin S. V. Maleyev E. I. Maltsev S. M. Mikirtychyants N. A. Tarasov G. V. Shcherbakov V. G. Grebinnik V. N. Duginov A. B. Lazarev V. G. Olshevski S. N. Shilov V. A. Zhukov I. I. Gurevich B. F. Kirillov A. I. Klimov B. A. Nikolski A. V. Pirogov A. N. Ponomarev V. A. Suetin 《Hyperfine Interactions》1991,64(1-4):415-419
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. 相似文献
3.
T. N. Mamedov D. G. Andrianov D. Herlach V. N. Gorelkin K. I. Gritsai V. N. Duginov O. Kormann J. Major A. V. Stoikov U. Zimmermann 《JETP Letters》2001,73(12):674-677
Results of studying the temperature dependence of the residual polarization of negative muons in crystalline silicon with germanium (9×10 19 cm ?3 ) and boron (4.1×10 18 , 1.34×10 19 , and 4.9×10 19 cm ?3 ) impurities are presented. It is found that, similarly to n-and p-type silicon samples with impurity concentrations up to ~10 17 cm ?3 , the relaxation rate ν of the magnetic moment of a μ Al acceptor in silicon with a high impurity concentration of germanium (9×10 19 cm ?3 ) depends on temperature as ν~T q , q≈3 at T=(5–30) K. An increase in the absolute value of the relaxation rate and a weakening of its temperature dependence are observed in samples of degenerate silicon in the given temperature range. Based on the experimental data obtained, the conclusion is made that the spin-exchange scattering of free charge carriers makes a significant contribution to the magnetic moment relaxation of a shallow acceptor center in degenerate silicon at T?30 K. Estimates are obtained for the effective cross section of the spin-exchange scattering of holes (σ h ) and electrons (σ e ) from an Al acceptor center in Si: σ h ~10?13 cm2 and σ e ~8×10?15 cm2 at the acceptor (donor) impurity concentration n a (n d )~4×1018 cm?3. 相似文献
4.
V. G. Grebinnik V. N. Duginov V. A. Zhukov S. Kapusta A. B. Lazarev V. G. Olshevsky V. Y. Pomjakushin S. N. Shilov D. T. Bezhitadze I. I. Gurevich B. F. Kirillov E. P. Krasnoperov B. A. Nikolsky A. V. Pirogov A. N. Ponomarev V. A. Suetin G. F. Tavadze I. P. Borovinskaya M. D. Nersesyan A. G. Peresada Y. F. Eltzev V. R. Karasik O. E. Omelyanovsky 《Hyperfine Interactions》1990,61(1-4):1093-1096
We report the results of μSR investigations of the ceramic samples La2-xSrxCuO4-σ (x=0.1, 0.15, 0.25) and ReBa2Cu3O7-σ (Re=Er, Ho, Y0.5Ho0.5) in the external magnetic field 0–800 Oe. The measurements were performed by the ZFC and FC methods. The irreversibility effects were studied at several temperatures by measuring the mean value and the width of the magnetic field distribution on the muon in the step by step procedure of increasing and subsequent decreasing of the external field. The temperature dependences of the magnetic penetration depth perpendicular to the basal plane λ⊥ were obtained. For the lanthanum sample with 0.15 of Sr its value at the zero temperature is λ⊥ (0)=2400 Å, for Er-Ba-Cu-O λ⊥ (0)=1600 Å. 相似文献
5.
V. G. Grebinnik V. N. Duginov V. A. Zhukov S. Kapusta A. B. Lazarev V. G. Olshevsky V. Y. Pomjakushin S. N. Shilov I. I. Gurevich B. F. Kirillov B. A. Nikolsky A. V. Pirogov A. N. Ponomarev V. A. Suetin I. P. Borovinskaya M. D. Nersesyan A. G. Persada Y. F. Eltzev V. R. Kapasik O. E. Omelyanovski 《Hyperfine Interactions》1990,61(1-4):1085-1088
6.
V. G. Grebinnik V. N. Duginov V. A. Zhukov S. Kapusta A. B. Lazarev V. G. Olshevsky V. Yu. Pomjakushin S. N. Shilov I. I. Gurevich B. F. Kirillov E. P. Krasnoperov B. A. Nikolsky A. V. Pirogov A. N. Ponomarev V. A. Suetin A. I. Morozov 《Hyperfine Interactions》1991,63(1-4):241-247
High temperature superconductors HoBa2Cu3O7−δ (T
c
≅93 K), Ho0.5Y0.5Ba2Cu3O7−δ (T
c
≅93 K) and ErBa2Cu3O7−δ (T
c
≅95 K) were investigated by the zero-field μSR-technique. The muon spin depolarisation rate connected with the fluctuation
frequency of rare-earth ion magnetic moments was measured. It was found that the samples with holmium show a fast increase
of the muon spin depolarisation rate at temperatures below 20 K, while in ErBa2Cu3O7−δ the depolarisation rate remains low in the whole temperature region studied (4.2 K-270 K). The sharp difference between the
behaviours of the muon spin depolarisation rate may be explained by the difference between the ground state of Ho3+ and Er3+ ions in the crystalline field of the lattice. 相似文献
7.
V. G. Grebinnik V. N. Duginov V. A. Zhukov S. Kapusta A. B. Lazarev V. G. Olshevsky V. Yu. Pomjakushin S. N. Shilov I. K. Ageenkova A. M. Brjazkalo B. F. Kirillov A. V. Pirogov B. A. Nikolsky A. N. Ponomarev V. N. Sumarokov A. G. Chistov S. Safrata J. Sebek D. Niznansky T. Hanslik H. Sichova 《Hyperfine Interactions》1991,63(1-4):117-122
8.
I.A. Krivosheev V.N. Duginov V.G. Grebinnik K.I. Gritsaj T.N. Mamedov V.N. Nikiforov V.G. Olshevsky V.Yu. Pomjakushin A.N. Ponomarev Yu.D. Seropegin V.A. Zhukov M. Baran H. Szymczak 《Hyperfine Interactions》1997,106(1-4):187-192
We have studied the magnetic spinel (Zn)[Fe2]O4 (T_ N\approx10.5\ K) and the non‐magnetic spinels (Zn)[Al2]O4, (Zn)[Ga2]O4, (Zn)[ZnTi]O4 and (Zn)[ZnSn]O4 , both with surface and decay channel muons. In (Zn)[Fe2]O4 the relaxation rate increases monotonically from room temperature down, typical for a paramagnet. Around 30 K, an additional, stronger damped signal appears which is the signature of short‐range ordered (SRO) regions. Their total volume fraction increases drastically towards T_ N (reaching 75%) and astonishingly, continues to be present also below T_ N where the rest of the material has become long‐range ordered. Longitudinal field μSR proves the SRO to be dynamic. In (Zn)[Al2]O4 and (Zn)[Ga2]O4 muon depolarization is caused solely by 27Al or 69,71Ga nuclear dipoles. In the inverse spinel (Zn)[ZnTi]O4, half of the implanted muons depolarize rapidly (\lambda\approx 3μs-1 at room temperature). This, together with repolarization behavior in longitudinal fields indicates that the muon in (Zn)[ZnTi]O4 undergoes a chemical reaction after implantation forming muonium. The fact that no such muonium formation occurred in another inverse spinel ( (Zn)[ZnSn]O4) means that the presence of muonium is not connected to the inverse structure but rather due to the presence of Ti which offers two d‐electrons to participate in the chemical bonding. Additional evidence for d‐electron participation is provided by 67Zn‐Mössbauer data which indicate unusual electron densities at the 67Zn nuclei only in (Zn)[ZnTi]O4. 相似文献
9.
10.
Journal of Applied and Industrial Mathematics - Under consideration is the following strongly NP-hard problem: Given a balanced complete bipartite graph with weights on the edges and a partition of... 相似文献