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1 Jul 1963

Volume 34, Issue 7, pp. 1837-2124

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Some Dielectric and Optical Properties of KD2PO4

T. R. Sliker and S. R. Burlage

J. Appl. Phys. 34, 1837 (1963); http://dx.doi.org/10.1063/1.1729696 (4 pages) | Cited 37 times

Online Publication Date: 9 June 2004

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The Curie point of KD2PO4 is found to be 222°±1°K, which is 9°K higher than previously reported. It is believed that the higher value is due to more complete deuteration. Other physical properties (at room temperature unless otherwise noted) are as follows: dielectric constant from 208° to 300°K; contour shearmode resonance‐frequency constant from 270° to 320°K; elastic compliance, s66E=165±3×10−12 m2∕N; piezoelectric constant, d36=58±2×10−12 C∕N; electromechanical coupling, k36=0.22±0.01; optical absorption between 200 and 2600 mμ for both KD2PO4 and KH2PO4 (the transmission of a 7.4‐mm‐thick KD2PO4 sample was greater than 50 percent from 400 to 1850 mμ); zero stress electro‐optic coefficient, r63=26.4±0.7×10−12 m∕V; lattice constants for both KD2PO4 and KH2PO4; and spontaneous polarization and coercive field from 150° to 222°K.

Influence of Anisotropy Dispersion on Magnetic Properties of Ni☒Fe Films

Mitchell S. Cohen

J. Appl. Phys. 34, 1841 (1963); http://dx.doi.org/10.1063/1.1729697 (7 pages) | Cited 25 times

Online Publication Date: 9 June 2004

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The dispersion of the magnetic anisotropy was monotonically increased in several Ni☒Fe films by subjecting them to increasingly severe heat treatments, and the room‐temperature magnetic properties were monitored after each anneal by Lorentz electron microscopy. A gradual transition towards increasingly anomalous properties in a single film was thereby observed. An increase, with annealing, of the magnetization ripple intensity, the measured angular anisotropy dispersion, and the wall coercive force Hw was found. After sufficient annealing, locking was seen upon reversal parallel to the easy axis; further annealing increased the locking‐wall density. The anisotropy field Hk monotonically decreased with annealing until the uniaxial character of the film was lost and it became a rotatable‐initial‐susceptibility (RIS) film. Reversal at azimuths away from the easy axis proceeded by labyrinth propagation after the early anneals, but by partial rotation after more severe annealing.

Strain‐Enhanced Diffusion in Metals. II. Dislocation and Grain‐Boundary Short‐Circuiting Models

A. L. Ruoff and R. W. Balluffi

J. Appl. Phys. 34, 1848 (1963); http://dx.doi.org/10.1063/1.1729698 (6 pages) | Cited 30 times

Online Publication Date: 9 June 2004

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Rapid diffusion along dislocation cores generally enhances the average bulk diffusion in a dislocated crystal. If each diffusing atom has at least several opportunities to make rapid excursions along various dislocation cores, Hart has shown that DT∕DT0 = 1+fDP∕DT0. DT is the average bulk diffusivity, DT0 is the diffusivity in the dislocation‐free lattice, f is the fraction of atoms in dislocation pipes, and DP is the diffusivity along dislocation pipes. Under these conditions, the diffusion‐penetration is increased by the short‐circuiting but the general shape of the penetration curve is unaffected. When the dislocations are static, each diffusing atom must visit a number of dislocations, and a necessary condition for the Hart relation to hold is 2(DT0t)☒>ld, where t is the diffusion time, and ld is the dislocation spacing. When this condition fails (for example, at lower temperatures), and when the dislocations are static, it is demonstrated that the amount of short‐circuiting is greatly reduced and that the dislocations become essentially ``clogged.'' However, if the dislocations move through the crystal, as they do in plastic deformation, the situation is quite different, since in this case the dislocations may visit the diffusing atoms rather than vice versa. In such cases, the short‐circuiting may again be randomized and the enhancement can be as large as (but no larger than) the result given by Hart, even if 2(DT0t)☒<ld. In certain cases, this type of short‐circuiting can produce very large relative enhancements.
A parallel development is given for short‐circuiting due to grain boundaries. In particular, it is shown that grain boundary migration and recrystallization, which occurs repeatedly during deformation of metals with low stacking fault energy, can, for temperatures equal to or less than about half the melting temperature, lead to a greatly increased diffusion coefficient without altering the general shape of the penetration curve.
A number of the results established in this work (Part II) are used in Part III (to be published) where a comprehensive interpretation of recent experimental work in the field is carried out. Part I consists of an analysis of point defect models for strain‐enhanced diffusion.

Electrical and Optical Properties of Crystalline Black Phosphorus

Douglas Warschauer

J. Appl. Phys. 34, 1853 (1963); http://dx.doi.org/10.1063/1.1729699 (8 pages) | Cited 25 times

Online Publication Date: 9 June 2004

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Polycrystalline black phosphorus has been produced by the Bridgman method of combined temperature and pressure and found to be p type with room‐temperature resistivity around one Ω‐cm, in agreement with the observations of previous workers. From 300° to 700°K, the resistivity can be fitted by an expression ρav=4.6×10−3 exp(0.35∕2kT) Ω‐cm, and the Hall data by (ReTmath)−1 = constant exp(−0.34∕2kT). The product Rσ can be represented in this temperature range by (Rσ)av = 9×105T−1.4 cm2∕V‐sec. The deviation from this law toward lower mobility observed by Keyes from 250° to 350°K does not occur in these samples. The resistivity continues to rise even near liquid‐helium temperature, and maxima in the Hall coefficient occur between 24° and 30°K. The low‐temperature Rσ products also exhibit maxima, and the magnitude of this product is small near liquid‐helium temperature. Although these characteristics are consistent with two‐band conduction, the relative appearance of the two sets of maxima is not consistent with a prediction of the simplest two‐band theory. An optical absorption edge is found in the 2‐ to 6‐μ region and its temperature dependence yields dW∕dT = 2.8×10−4 eV∕deg. A sharp absorption peak observed near 21 μ moves to longer wavelengths with increasing temperature at a rate dW∕dT = −2×10−6 eV∕deg. At helium temperature the ac photoconductive response is substantially flat from one to 20 μ. At nitrogen temperature the response is peaked between 4 and 5 μ, while at room temperature a peak is observed in the same wave‐length range but the sensitivity is considerably less.

Microwave Measurements of Moving Striations in a DC Glow Discharge

K. F. Sodomsky

J. Appl. Phys. 34, 1860 (1963); http://dx.doi.org/10.1063/1.1729700 (7 pages) | Cited 7 times

Online Publication Date: 9 June 2004

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The effects of moving striations in a glow discharge on microwave standing‐wave patterns in a waveguide containing the discharge were measured. The data yielded estimates of the longitudinal variation of electron density along a striation which were compared to measured light intensity variations. It was found that there were large variations in both electron density and brightness with the brightness maximum just to the cathode side of the electron density maximum. These results are compared to the results of other investigations and some points of disagreement noted.

Dislocation Behavior and the Yield Stress in Neutron‐Irradiated MgO

Paul F. Stablein

J. Appl. Phys. 34, 1867 (1963); http://dx.doi.org/10.1063/1.1729701 (5 pages) | Cited 9 times

Online Publication Date: 9 June 2004

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Mechanical property measurements on neutron‐irradiated MgO single crystals show that hardening is caused by fast neutrons exclusively. Microhardness measurements, followed by etching to reveal dislocation distribution, permit an analysis of plastic flow even on samples which are so embrittled by the irradiation (with a dose of 1019 nvt) that it has not been possible to bend them. As determined from 3‐point bending experiments on samples annealed at temperatures up to 1200°C, it does require an increasingly higher stress to form a dislocation (source hardening) as well as to move it through the damaged lattice (friction hardening). The type of defects responsible for such behavior are discussed.

Attenuation of Pure Elastic Modes in NaCl Single Crystals

Emmanuel P. Papadakis

J. Appl. Phys. 34, 1872 (1963); http://dx.doi.org/10.1063/1.1729702 (5 pages)

Online Publication Date: 9 June 2004

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Pulse‐echo ultrasonic attenuation measurements were made for longitudinal and transverse waves in the [100], [110], and [111] propagation directions in NaCl specimens cut from a single boule. The attenuation α was proportional to the orientation factor Ω (relating the resolved stress on the slip system of the crystal to the applied stress), and to the square of the frequency f. Under x‐ray irradiation, α decreased for modes with Ω=≠0 but remained constant where Ω=0. Dislocation damping is considered to cause the loss.

Tunneling Current Density as a Function of Crystallographic Polarity

Miriam T. Minamoto and Hilary T. Malafi

J. Appl. Phys. 34, 1876 (1963); http://dx.doi.org/10.1063/1.1729703 (6 pages) | Cited 3 times

Online Publication Date: 9 June 2004

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Esaki diodes using the A and B or opposite {111} faces of zinc‐doped gallium antimonide were fabricated using tin—tellurium spheres. Diodes made by alloying to the B face exhibit approximately an order‐of‐magnitude higher peak tunneling current density than those made by alloying to the A face. Differences are found in the junction geometries. Junctions fabricated by alloying to the B or {111} face are generally planar and delineation of these is pronounced, suggesting enhanced impurity concentration in their recrystallized regions. A or {111} face alloyed junctions are curved and tend to be obscurely delineated. The capitance per unit area of the B diodes was approximately twice that of the A diodes. Thus Jp∕C values were typically 5–7 times higher for the B diodes. Calculations indicate, for typical A and B diodes, excess carrier concentrations 4.0×1018 and 1.5×1019∕cm3, respectively. The higher tunneling current, the higher capacitance, and enhanced delineation of the planar B junction are apparently the effects of higher impurity concentration in the regrowth region due to the difference of the segregation coefficient of tellurium in gallium antimonide with crystallographic direction of growth.

Observations on Work‐Hardening and Fracture of Pure Polycrystalline Zinc in Tension

R. Kamel and F. A. Bessa

J. Appl. Phys. 34, 1881 (1963); http://dx.doi.org/10.1063/1.1729704 (5 pages) | Cited 7 times

Online Publication Date: 9 June 2004

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High‐purity zinc wires of different grain sizes were subjected to increasing tensile loading at different temperatures, and the associated changes in length, internal friction, and shear modulus were simultaneously measured. The work‐hardening coefficient was found to be parabolic and to decrease with increase of grain size and temperature. This was interpreted in terms of the associated variations of the dislocation slip distance. An internal friction peak was observed at low stresses before excessive slip took place, and was attributed to the freeing and subsequent locking of the loosely pinned dislocations under the action of the applied stress. In fine‐grained samples, a rise in the shear modulus was also observed and was attributed to the dislocations created by activated Frank—Read sources, which pile up against grain boundaries. The grain‐boundary fracture surface energy, calculated from the observed dependence of the fracture and yield stresses on grain size, amounted to 1280 ergs∕cm2 at room temperature.

Self‐Pinch Instabilities in Solid Sodium

R. M. Henson and M. Eisner

J. Appl. Phys. 34, 1886 (1963); http://dx.doi.org/10.1063/1.1729705 (2 pages)

Online Publication Date: 9 June 2004

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Taylor‐type instabilities have been observed using sodium as a magnetohydrodynamic model of plasma. The wavelengths were found to be in fair agreement with the theory of Kruskal and Schwarzschild.

Relation of Equilibrium Phase‐Transition Pressure to Ionic Radii

V. S. Stubican and Rustum Roy

J. Appl. Phys. 34, 1888 (1963); http://dx.doi.org/10.1063/1.1729706 (3 pages) | Cited 11 times

Online Publication Date: 9 June 2004

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Pressure‐temperature equilibria curves for a series of some 20 rare‐earth arsenates and rare‐earth vanadates which undergo the reconstructive transition zircon (Zr SiO4) ⇆ scheelite (CaWO4) type structure in the region 10 000–60 000 atm were obtained. From these curves, a set of data were extracted representing (with a fair approximation to corresponding states) the change of equilibrium pressure for a transition as a function of the radius of the rare‐earth ion. The result is a V‐shaped curve for both vanadates and arsenates showing a minimum transformation pressure near Dy3+ or Ho3+. An interesting even‐odd effect is noted.

Fluctuations in Hot Tungsten Filaments

James J. Brophy

J. Appl. Phys. 34, 1890 (1963); http://dx.doi.org/10.1063/1.1729707 (4 pages) | Cited 1 time

Online Publication Date: 9 June 2004

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The high‐frequency spectral noise voltage appearing across a metallic conductor electrically heated to high temperatures is experimentally found to be in agreement with the Nyquist theorem even though the conductor is far from thermodynamic equilibrium. Furthermore, because of the thermal origin of the nonlinearities in the current‐voltage characteristic the proper value of resistance to use in the Nyquist expression corresponds to the voltage∕current ratio, rather than the differential resistance at the operating point. At frequencies below that corresponding to the thermal time constant of the conductor, an additional noise voltage caused by temperature fluctuations is detected. The observed magnitude and spectrum of this noise voltage is in very good agreement with a simple calculation of temperature fluctuations due to heat conduction.

Velocity Modulation of Propagating Waves

Rolf Landauer

J. Appl. Phys. 34, 1893 (1963); http://dx.doi.org/10.1063/1.1729708 (4 pages) | Cited 5 times

Online Publication Date: 9 June 2004

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Waves moving through a medium in which the wave velocity is a function of time and space suffer frequency changes. If the velocity modulation is small and adiabatic, very elementary kinematic considerations define these frequency changes. For a uniformly moving velocity pattern the frequency change suffered by a portion of the wave is shown to depend only on the wave velocity at the input and output end of the modulating system, and not on the intermediate velocities experienced by the wave. Electro‐optic modulation and deflection experiments are treated in this framework. The paper is intended to present a particularly simple viewpoint, and does not arrive at really new results.

Modulated Langmuir Probe Characteristics

F. W. Crawford

J. Appl. Phys. 34, 1897 (1963); http://dx.doi.org/10.1063/1.1729709 (6 pages) | Cited 41 times

Online Publication Date: 9 June 2004

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The presence of fluctuations in the discharge parameters introduces errors into Langmuir probe measurements. Previous work by Garscadden and Emeleus considered the effects of fluctuations in the individual parameters. In this paper a generalized small‐amplitude theory of the effects of these fluctuations is given and also a large signal theory for single‐frequency oscillations. The results of Garscadden and Emeleus can be deduced from these, but additional terms are predicted due to cross modulation occurring when the various fluctuations are correlated. The large signal theory has been checked experimentally in a mercury‐vapor discharge at a pressure of about 1 μ. Further experimental measurements with injected broadband noise signals confirm certain features of the generalized theory. The errors caused by fluctuations are discussed and it is concluded that although electron temperatures may still be measured accurately in their presence, serious errors can be incurred in the measurement of electron saturation current and number density.

Heat‐Wave Methods for the Measurement of Thermal Diffusivity

M. Cutler and G. T. Cheney

J. Appl. Phys. 34, 1902 (1963); http://dx.doi.org/10.1063/1.1729710 (8 pages) | Cited 9 times

Online Publication Date: 9 June 2004

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A simple method for measuring thermal diffusivity is considered. It consists in suddenly heating one end of a sample and measuring the time it takes for a heat wave to arrive at the other end. This paper considers the application of this method for two kinds of boundary conditions relating to the heat input. These conditions correspond to step‐function heating (a) by radiation and (b) by a good contact to a constant‐temperature heat source, such as liquid metal.
In addition to consideration of the effects on the analytic solution due to radiation heat loss, other factors which affect the accuracy and sensitivity of the technique are discussed. The heat‐wave method is related to many other techniques for measuring thermal diffusivity, ranging from Angstrom's original method to several pulse heating techniques which have been described recently. The interrelationships between these different techniques are discussed.

Temperature and Finite Pulse‐Time Effects in the Flash Method for Measuring Thermal Diffusivity

J. A. Cape and G. W. Lehman

J. Appl. Phys. 34, 1909 (1963); http://dx.doi.org/10.1063/1.1729711 (5 pages) | Cited 122 times

Online Publication Date: 9 June 2004

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The flash technique for measuring thermal diffusivity is analyzed for the case of a cylindrical‐shaped specimen of radius r0 and thickness a to determine the effects of radiation at high temperatures, finite duration of the heat pulse, and the feasibility of low temperature measurements. It is found that the flash diffusivity method is useful in two complementary limits: (1) pulse time τ short compared to the characteristic thermal response time tc, (2) τ∕tc of the order 1 to 10. The former case corresponds to the original description of Parker, Jenkins, and Abbott, while the latter case is suitable at very low temperatures. Moreover, it is shown that there is an optimum specimen thickness a for a given material and pulse time τ, in the sense that a higher temperature can be reached before any corrections have to be made to the Parker et al. analysis.

Acceptors in Donor‐Doped GaAs Resulting from Li Diffusion

C. S. Fuller and K. B. Wolfstirn

J. Appl. Phys. 34, 1914 (1963); http://dx.doi.org/10.1063/1.1729712 (7 pages) | Cited 25 times

Online Publication Date: 9 June 2004

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Experiments have been carried out on Te‐doped (∼1–3×1018 cm−3) GaAs crystals in which changes in n are measured when Li is introduced by diffusion and again after the Li is removed. The amounts of Li removed are determined by chemical analyses. It is found that two Li atoms introduced cause a loss of one electron, corresponding to a (Li+Li=) pair. Acceptors remain during the removal of Li which are postulated to be Ga vacancies. The kinetics of the disappearance of the ``vacancies'' have been investigated. The process appears to be diffusion controlled with an activation energy corresponding to 5–6 eV. The equilibria reached show an increasing ``vacancy'' solubility with decreasing temperature. A model in which Ga vacancies form stable pairs with Te atoms is discussed.

Dynamics of a Viscoelastic Wear Particle between Sliding Surfaces

W. D. May, E. L. Morris, and D. Atack

J. Appl. Phys. 34, 1920 (1963); http://dx.doi.org/10.1063/1.1729713 (9 pages)

Online Publication Date: 9 June 2004

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It is predicted theoretically that because of its time‐dependent mechanical properties, the rolling behavior of a wear fragment of viscoelastic material trapped between two moving surfaces is complex. If the moving surfaces are smooth and unlubricated, the fragment may either roll with a velocity equal to half the relative velocity between the surfaces, or it may reach a terminal rolling velocity beyond which increases in surface speed cannot drive it. If the surfaces are lubricated, the tractive force tending to roll the fragments arises from the friction of surface asperities sliding through the fragment. The rolling behavior then depends on the ratio of the size of the asperity to the size of the fragment. A critical value of this ratio exists. Above it, the fragment rolls at a velocity always slightly less than half that of the surfaces because of slip. Below the critical ratio, the fragment cannot be driven beyond a certain maximum velocity. Slip always takes place between the fragment and the surface, and increases with increasing surface velocity. Beyond the maximum rolling velocity, an increase of surface velocity leads to a decrease in the rolling velocity of the fragment.

Theory of Scattering for Diffusion‐Controlled Phase Separations

Martin Goldstein

J. Appl. Phys. 34, 1928 (1963); http://dx.doi.org/10.1063/1.1729714 (7 pages) | Cited 14 times

Online Publication Date: 9 June 2004

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A quantitative theory of the scattering from systems in which a precipitating phase is undergoing diffusion‐controlled growth is worked out by means of a Fourier transform method, and is applied to experimental data on light scattering from phase‐separated glasses. The theory predicts an initial inverse eighth‐power dependence of turbidity on wavelength, a great excess of backward scattering over forward scattering, and under certain conditions a minimum in the plot of intensity against scattering angle, all of which are in agreement with observation.

In‐Pile Hall Coefficient and Conductivity Measurements on Zone‐Refined, p‐Type Silicon

G. C. Bailey and C. M. Williams

J. Appl. Phys. 34, 1935 (1963); http://dx.doi.org/10.1063/1.1729715 (7 pages) | Cited 2 times

Online Publication Date: 9 June 2004

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The Hall coefficient and conductivity have been measured during pile‐irradiation for a number of zone‐refined, p‐type silicon crystals with initial resistivities of 1, 8, and 100 Ω‐cm. To supply the magnetic field for the Hall measurements, a small electromagnet was used. The conductivity of zone‐refined silicon shows much faster changes with irradiation than pulled silicon samples of equivalent resistivity. The 100‐Ω‐cm samples exhibit a monotonic nonlinear decrease of lnσ, conductivity, vs ϕf, integrated fast flux, whereas the other samples with initial Fermi levels closer to the valence band have one or two regions of linear decrease in lnσ vs ϕf before the nonlinear decrease region is observed. The Hall mobility for the 100‐Ω‐cm samples decreases and becomes negative as a result of the carrier density decreasing with irradiation. In the case of the 8‐Ω‐cm sample, the Hall mobility decreases with irradiation whereas the 1‐Ω‐cm sample shows no change in Hall mobility with irradiation up to the maximum integrated flux used in the present experiment. The origins of the dependence of lnσ on ϕf as well as the behavior of the Hall coefficient and Hall mobility with irradiation are discussed.

Surface Lines on Soda‐Lime Glass Slides

G. R. Stilwell and D. B. Dove

J. Appl. Phys. 34, 1941 (1963); http://dx.doi.org/10.1063/1.1729716 (4 pages)

Online Publication Date: 9 June 2004

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It has been found that a remarkable line structure may be developed on the surface of soda‐lime glass slides by treatment in a hot detergent solution (2% Alconox). The lines are produced by an etching process which exposes ridges or cords of less soluble material that have been introduced into the surface layer by the manufacturing procedure of drawing the glass through an orifice (Fourcault process). Details are given of etch rates, size and distribution of the ridges, and of the effect of annealing treatments.
The possibility of the inadvertent production of an anisotropic surface structure is of some importance since soda‐lime microscope slides are frequently used as substrates for vapor deposition processes. Preliminary experiments to examine the effect of the line structure on vapor deposited Permalloy films are discussed.

Average Neutron Energy of Reactor Spectra and Its Influence on Displacement Damage

A. D. Kantz

J. Appl. Phys. 34, 1944 (1963); http://dx.doi.org/10.1063/1.1729717 (9 pages) | Cited 3 times

Online Publication Date: 9 June 2004

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The average energy of the neutron spectrum for reactor sources may be evaluated to good approximation by a threshold‐reaction technique using the activation of only two threshold‐reaction foils. For plutonium (effective threshold 0.001 MeV) and sulfur (effective threshold 3.0 MeV) foils the average energy of a reactor spectrum is found to be Ē=7.42R+0.30 MeV, where R is the ratio of the number flux measured above the sulfur threshold to the number flux measured above the plutonium threshold.
The carrier removal rate per unit flux has been measured for vacuum floating zone n‐type silicon (phosphorus‐doped) as a function of the average energy of the reactor spectrum as measured by the two‐foil method. Resistivities of 1‐, 10‐, and 100‐Ω‐cm samples were used in these irradiations at seven different reactor spectra. The carrier removal rate is found to be proportional to the average energy of the neutron spectrum. The highest average energy realized in the experimental work was 2.3 MeV.

Dislocation‐Impurity Interactions and Strain Aging in AgCl

M. N. Kabler, M. G. Miller, and L. M. Slifkin

J. Appl. Phys. 34, 1953 (1963); http://dx.doi.org/10.1063/1.1729718 (5 pages) | Cited 6 times

Online Publication Date: 9 June 2004

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Strain aging in silver chloride single crystals containing a few parts in 105 polyvalent metal impurity has been studied over the temperature range −12° to 51°C. At room temperature, the aging process requires of the order of half an hour to go to completion. The measured activation energy for the aging rate is 0.46±0.06 eV. The maximum stress increment due to aging decreases with increasing temperature with an effective activation energy of 0.1 eV. On the basis of the kinetics of the process, it is demonstrated that the dislocation pinning giving rise to strain aging is due to the migration to the dislocations of the impurity ions themselves rather than the vacancies they introduce. Sharp upper yield points have been observed; they are discussed in terms of current concepts of dislocation multiplication and unpinning.

Resistance of Elastically Deformed Shallow p‐n Junctions. II

W. Rindner and I. Braun

J. Appl. Phys. 34, 1958 (1963); http://dx.doi.org/10.1063/1.1729719 (13 pages) | Cited 23 times

Online Publication Date: 9 June 2004

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An effect of large anisotropic stresses to lower the resistance of shallow p‐n junctions reversibly by several orders of magnitude has been extensively investigated. Even though large stresses have been used it was found that their anisotropies were of greater significance than their magnitudes. The effect was found to increase strongly with decreasing junction depth. Of the crystal planes studied in Ge, the effect was largest with junctions lying in the (111) planes and smallest with junctions in the (100) planes. In both Ge and Si the effect increased with increasing temperatures. Stress‐frequency response was observed from dc to 100 kc. The same effect in transitors caused reversible changes in collector current by factors up to nearly 1000 for a constant emitter current. Stress and strain analyses indicated large energy‐gap changes with pronounced extrema. At the present stage, none of the known stress effects on the resistance of homogeneous semiconductors or junctions could be satisfactorily correlated with the magnitude and the various manifestations of the present stress effect. A tentative model is considered, based on a stress controlled generation‐recombination rate of carriers due to generation and elastic distortion of dislocations.

CsCl‐Type Compounds in Binary Alloys of Rare‐Earth Metals with Gold and Silver

C. C. Chao, H. L. Luo, and P. Duwez

J. Appl. Phys. 34, 1971 (1963); http://dx.doi.org/10.1063/1.1729720 (3 pages) | Cited 33 times

Online Publication Date: 9 June 2004

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In binary alloys of silver with Sm, Tb, Ho, and Tm, and of gold with Y, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, and Tm, intermediate phases containing stoichiometric proportions of the two metals were found to crystallize into the CsCl (B2)‐type structure. The lattice parameters of these phases are reported and a correlation has been found between these lattice parameters and the trivalent ionic radii of the rare‐earth metals.
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