Experimental study of manifestations of resonance scattering of conduction electrons on transition-element impurities in mercury selenide

The given work is devoted to the experimental proof of existing the spontaneous spin polarization of the donor electron system of 3d-transition element impurity atoms of low concentration (<1 at.%) in a mercury selenide crystal. For this purpose there have been measured the dependences of the magnetization on the magnetic field strength. As a result of the analysis of the obtained dependences, there were extracted the impurity contributions, which are described by the magnetization curves typical of the ferromagnets, and by the magnetic parameters conforming to the spontaneous magnetism of the systems under study, which are unambiguously related to the donor conduction electrons of the outer d-shells of impurity atoms. By its nature, according to the developed theoretical concepts, the spontaneous spin polarization manifests itself in exchange interaction, taking place in hybridizing the electronic states of the impurity atom and the conduction band ones of the crystal.

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Experimental Study of Acoustic Wave Propagation through Resonating Devices

Building Acoustics ◽

10.1177/1351010x9800500104 ◽

1998 ◽

Vol 5 (1) ◽

pp. 39-55

Author(s):

Y.K. Lai ◽

C.F. Ng

Keyword(s):

Experimental Data ◽

Experimental Study ◽

Function Method ◽

Transmission Loss ◽

Stop Band ◽

Resonance Scattering ◽

Acoustic Wave Propagation ◽

Transfer Function Method ◽

Bandwidth Control ◽

Filter Effects

The acoustic filter effects of periodic obstructions in a square section of duct are studied experimentally. The two-microphone transfer function method is employed to measure the transmission loss across the periodic elements of different profiles. The experiments aim to measure the Bragg Stop Band and the Resonance Scattering Stop Band and their interaction. The experimental data show that the Bragg effect is spatial dependent. The Resonance Scattering Stop Band is strongly affected by obstacles and demonstrates a possibly useful interaction between the Bragg Stop Band and the Resonance Scattering Stop Band. Results also indicate that for specific situations, the overall Resonance Scattering Stop Band contribution can be dominant and effective, both in terms of magnitude and bandwidth control. The asymmetric placement of the obstructing elements is shown to be nonreversible.

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LOCAL IMPURITY STATES IN ANTIFERROMAGNETIC Cr-ALLOYS

International Journal of Modern Physics B ◽

10.1142/s0217979293001347 ◽

1993 ◽

Vol 07 (01n03) ◽

pp. 638-643 ◽

Cited By ~ 5

Author(s):

V.YU. GALKIN

Keyword(s):

Low Temperatures ◽

Energy Gap ◽

Density Wave ◽

Spin Density Wave ◽

Resonant Scattering ◽

Resonance Scattering ◽

Residual Resistivity ◽

Impurity States ◽

Conduction Electrons ◽

Temperature Resistivity

The concept of local impurity states within the energy gap of a spin-density-wave (SDW) system is introduced. It is shown that resonant scattering of conduction electrons at these states may lead to greatly enhanced low-temperature resistivity. This impurity resonance scattering (IRS) model is employed to explain the variation of residual resistivity and temperature dependence of resistivity at low temperatures of Cr-Fe and Cr-Si systems on V and Mn doping and application of high pressure.

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THE EFFECT OF RESONANCE SCATTERING ON THE CRITICAL TEMPERATURE OF ANISOTROPIC SUPERCONDUCTORS

Canadian Journal of Physics ◽

10.1139/p67-006 ◽

1967 ◽

Vol 45 (1) ◽

pp. 37-45 ◽

Cited By ~ 9

Author(s):

M. J. Zuckermann ◽

A. D. Singh

Keyword(s):

Critical Temperature ◽

Transition Metal ◽

Impurity Concentration ◽

Resonance Scattering ◽

Anisotropic Scattering ◽

Cross Term ◽

Conduction Electrons ◽

Metal Impurities ◽

Transition Metal Impurity ◽

Comparison With Experiment

In a previous paper, the effect of a nonmagnetic resonant d orbital (bound to a transition-metal impurity) on a simple isotropic superconductor was discussed. It was shown that the critical temperature Te of such an alloy suffered an initial linear decrease proportional to the impurity concentration NI. The resulting curve of Te versus NI remains linear for experimentally realizable values of the impurity concentration. However, this is not borne out experimentally and one reason for the discrepancy is that the anisotropy of the superconductor was not taken into account theoretically. In this paper, it is shown that the change in Te due to the presence of nonmagnetic transition-metal impurities is given by the sum of three terms, as follows: (a) the isotropic term due to the interaction of the d orbital with the conduction electrons found in the previous paper, (b) the usual term due to the "anisotropic effect" of Markowitz and Kadanoff (1963), and (c) a cross term between the resonance scattering and the anisotropic scattering. The term (c) is shown to be very small compared with (a) and (b) and hence the procedure for comparison with experiment used by Boato et al. (1966) is justified in our approximation.

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Diffuse scattering of the conduction electrons of a metallic substrate by an adsorbate: an experimental study using synchrotron infrared radiation

10.1117/12.366644 ◽

1999 ◽

Author(s):

Paul Dumas ◽

Matthias Hein ◽

Andreas Otto ◽

Gwyn P. Williams

Keyword(s):

Experimental Study ◽

Infrared Radiation ◽

Diffuse Scattering ◽

Metallic Substrate ◽

Conduction Electrons

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Thermo-electricity at low temperatures. IX. The transition metals as solute and solvent

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1962.0054 ◽

1962 ◽

Vol 266 (1325) ◽

pp. 161-184 ◽

Cited By ~ 104

Keyword(s):

Experimental Data ◽

Transition Metals ◽

Low Temperatures ◽

Transition Element ◽

Present Theory ◽

Parent Metal ◽

Transition Elements ◽

Thermo Electric ◽

Conduction Electrons ◽

Spin Dependent Scattering

Transition metals (in particular Cr, Mn, Fe, Co and Ni) present as solutes give rise to highly anomalous thermo-electric powers and unusual resistive behaviour at very low temperatures. Following an outline of the theories which have been proposed to account for this behaviour, experimental data are presented on alloys of gold as parent metal with transition element solutes down to very low temperatures, and the results compared broadly with the conclusions of present theory. It is generally believed that the fundamental origin of the anomalous thermo-electric behaviour lies in the spin-dependent scattering of conduction electrons by the magnetic solute ions. Experimental data are also presented of the thermo-electric behaviour down to very low temperatures of alloys of the transition metals Pd and Pt with both transition elements and non-transition elements as solutes.

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Generation of 4H and 6H Structures During the Hexagonal-Rhombohedral Transformation in Dy2Co17

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100113810 ◽

1975 ◽

Vol 33 ◽

pp. 38-39

Author(s):

C. W. Allen ◽

D. L. Kuruzar

Keyword(s):

Elevated Temperatures ◽

Layer Structure ◽

Transition Element ◽

Temperature Structure ◽

Allotropic Transformation ◽

Layer Plane ◽

Planar Defects ◽

Topologically Close Packed ◽

Transformation Mechanisms ◽

Shear Transformation

The rare earth/transition element intermetallics R2T17 are essentially topologically close packed phases for which layer structure models have already been presented. Many of these compounds are known to undergo allotropic transformation of the type at elevated temperatures. It is not unexpected that shear transformation mechanisms are involved in view of the layering character of the structures. The transformations are evidently quite sluggish, illustrated in furnace cooled Dy2Co17 by the fact that only rarely has the low temperature rhombohedral form been seen. The more usual structures observed so far in furnace cooled alloys include 4H and 6H in Dy2Co17 (Figs. 1 and 2) . In any event it is quite clear that the general microstructure is very complicated as a consequence of the allotropy, illustrated in Fig. 3. Numerous planar defects in the layer plane orientation are evident as are non-layer plane defects inherited from a high temperature structure.

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Experimental study on the restoration from a tilt-azimuth series for improvement in resolution

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010013955x ◽

1995 ◽

Vol 53 ◽

pp. 636-637

Author(s):

Norio Baba ◽

Norihiko Ichise ◽

Syunya Watanabe

Keyword(s):

Experimental Study ◽

Spherical Aberration ◽

Incident Beam ◽

Optical Parameters ◽

Beam Tilting ◽

Illumination Method ◽

Restoration Method ◽

Illumination Mode

The tilted beam illumination method is used to improve the resolution comparing with the axial illumination mode. Using this advantage, a restoration method of several tilted beam images covering the full azimuthal range was proposed by Saxton, and experimentally examined. To make this technique more reliable it seems that some practical problems still remain. In this report the restoration was attempted and the problems were considered. In our study, four problems were pointed out for the experiment of the restoration. (1) Accurate beam tilt adjustment to fit the incident beam to the coma-free axis for the symmetrical beam tilting over the full azimuthal range. (2) Accurate measurements of the optical parameters which are necessary to design the restoration filter. Even if the spherical aberration coefficient Cs is known with accuracy and the axial astigmatism is sufficiently compensated, at least the defocus value must be measured. (3) Accurate alignment of the tilt-azimuth series images.

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