Is potassium a simple metal?

1982 ◽  
Vol 60 (5) ◽  
pp. 693-702 ◽  
Author(s):  
Nathan Wisbr
Keyword(s):  
Electrical Resistivity ◽  
Electron Scattering ◽  
Phonon Scattering ◽  
Measured Data ◽  
The Other ◽  
Simple Metal ◽  
Temperature Dependent ◽  
Dependent Part ◽  
Simple Behavior ◽  
Electron Phonon Scattering

The temperature-dependent part of the electrical resistivity ρ(T) of a metal consists of the sum of two terms, one term being due to electron–phonon scattering ρcp(T) and the other term being due to electron–electron scattering ρcc(T). One may write[Formula: see text]where θD, is the Debye temperature of the metal and the coefficients C and A give the magnitudes of ρcp(T) and ρcc(T), respectively. For a metal whose electrical resistivity exhibits "simple" behavior, it had been expected that the measured data for ρ(T) would have the following properties. (i) The function f(T/θD) should approach (T/θD) for [Formula: see text]. (ii) The magnitude of the coefficient C should be the same, or nearly so, for all measured samples. (iii) The magnitude of the coefficient A should be the same, or nearly so, for all measured samples.The low-temperature ρexpt(T) data for potassium, which has by now been measured for many samples, exhibit none of these three properties. A discussion will be presented of the reasons for this "non-simple" behavior of ρexpt(T) for potassium.

MONTE CARLO SIMULATION OF THE DC SIZE EFFECT IN THIN FILMS

1995 ◽  
Vol 06 (02) ◽  
pp. 223-232
Author(s):  
R.I. BOUGHTON ◽  
ZHIPING FENG
Keyword(s):  
Monte Carlo ◽  
Electron Scattering ◽  
Phonon Scattering ◽  
Numerical Technique ◽  
Method Comparison ◽  
Boundary Scattering ◽  
Temperature Dependent ◽  
Relaxation Time Approximation ◽  
Dependent Part ◽  
The Monte Carlo Method

The Monte Carlo method is used to study the effect of boundary scattering on the temperature dependent part of the resistivity of thin metal films. A computational scheme is used that realistically simulates electron scattering mechanisms in the semi-classical context. As a test of the accuracy of the method, comparison is made between the present method at absolute zero (impurity and boundary scattering only) and the analytical results of Fuchs, which rely on the relaxation time approximation (RTA). The inclusion of phonon scattering provides a measure of the size induced deviations from Matthiessen’s Rule (SIDMR). At low temperatures phonon scattering cannot be adequately described using the RTA and the numerical technique presented shows good promise of overcoming this problem. Calculated SIDMR results are compared with some recent data on Al and Ga films.

TEMPERATURE DEPENDENCE BEHAVIOR OF ELECTRICAL RESISTIVITY IN NOBLE METALS AT LOW TEMPERATURES

2014 ◽  
Vol 5 (3) ◽  
pp. 982-992 ◽  
Author(s):  
M AL-Jalali
Keyword(s):  
Experimental Data ◽  
Electrical Resistivity ◽  
Temperature Dependence ◽  
Concentration Dependence ◽  
Low Temperatures ◽  
Noble Metals ◽  
Phonon Scattering ◽  
Theoretical Models ◽  
Residual Resistivity ◽  
Electron Phonon Scattering

Resistivity temperature – dependence and residual resistivity concentration-dependence in pure noble metals(Cu, Ag, Au) have been studied at low temperatures. Dominations of electron – dislocation and impurity, electron-electron, and electron-phonon scattering were analyzed, contribution of these mechanisms to resistivity were discussed, taking into consideration existing theoretical models and available experimental data, where some new results and ideas were investigated.

THE LOW-TEMPERATURE THERMAL CONDUCTIVITY, ELECTRICAL RESISTIVITY, AND THERMOELECTRIC POWER OF DILUTE SILVER ALLOYS WITH MANGANESE

1966 ◽  
Vol 44 (10) ◽  
pp. 2293-2302 ◽  
Author(s):  
H. L. Malm ◽  
S. B. Woods
Keyword(s):  
Thermal Conductivity ◽  
Electrical Resistivity ◽  
Low Temperature ◽  
Thermoelectric Power ◽  
Electron Scattering ◽  
The Other ◽  
Temperature Measurements ◽  
Silver Alloys ◽  
Temperature Range ◽  
Dilute Alloy

Low-temperature measurements of electrical resistivity, thermal conductivity, and thermoelectric power on silver alloys containing 0.005, 0.067, 0.11, and 0.31 at.% of manganese are reported. The same specimens were used for the measurement of all properties over the temperature range from 2 to 25 °K. The well-known minimum and maximum are observed in the electrical resistivity of the three more concentrated alloys and the minimum is visible in the most dilute alloy near the lowest temperatures of measurement. Associated effects are observed in the other properties and their possible relationship to theoretical electron scattering mechanisms, particularly that of Kondo, is discussed.

Amplitude of the de Haas—van Alphen effect in mercury

1972 ◽  
Vol 329 (1576) ◽  
pp. 17-34 ◽  
Keyword(s):  
Temperature Dependence ◽  
Debye Temperature ◽  
Phonon Scattering ◽  
Many Body ◽  
Temperature Dependent ◽  
Many Body Theory ◽  
Logarithmic Plot ◽  
Paradoxical Result ◽  
Body Theory ◽  
Electron Phonon Scattering

The amplitude of the de Haas-van Alphen oscillations in mercury has been studied at temperatures between 1 and 17 K and fields between 20 and 90 T. Because of the low Debye temperature of mercury, the Dingle temperature X might be expected to increase appreciably with temperature because of increased scattering of electrons by phonons. Such a temperature dependent X would also cause the appropriate logarithmic plot of amplitude against temperature to depart appreciably from linearity. Measurements of X as a function of temperature and of the temperature dependence of amplitude at a number of fields have however provided no evidence of any appreciable temperature dependence of X . This apparently paradoxical result turns out to be explicable by a recent many-body theory due to Engelsberg & Simpson of the effects of electron-phonon scattering on the de Haas-van Alphen amplitude.

THERMOELECTRICITY OF Ca2.9Ce0.1Co4O9+δ BASED NANOCOMPOSITES WITH Cu2O NANOINCLUSION

2013 ◽  
Vol 27 (22) ◽  
pp. 1350108
Author(s):  
FANG JU LI
Keyword(s):  
Thermal Conductivity ◽  
Electrical Resistivity ◽  
Energy Harvesting ◽  
Thermoelectric Properties ◽  
Thermoelectric Materials ◽  
Phonon Scattering ◽  
Temperature Dependent ◽  
Resistivity Measurements ◽  
Carrier Scattering ◽  
Scattering Centers

Ca 2.9 Ce 0.1 Co 4 O 9+δ/x wt% Cu 2 O nanocomposites have been studied as the thermoelectric materials for energy harvesting purpose. We evaluate the thermoelectric properties of the composites through temperature dependent thermopower, thermal conductivity and resistivity measurements. It is found that the introduction of Cu 2 O nanoparticles serves as phonon scattering centers, which reduces the thermal conductivity. The nanoinclusions contribute to a remarkable increase in electrical resistivity due to enhanced carrier scattering. As a result, Cu 2 O nanoinclusions do not succeed in improving ZT of Ca 2.9 Ce 0.1 Co 4 O 9+δ material.

Normal metal point contacts

1982 ◽  
Vol 60 (5) ◽  
pp. 740-745 ◽  
Author(s):  
H. van Kempen
Keyword(s):  
Electron Scattering ◽  
Kondo Effect ◽  
Phonon Scattering ◽  
Point Contact ◽  
High Current ◽  
Point Contacts ◽  
Paramagnetic Impurities ◽  
Normal Metals ◽  
Current Densities ◽  
Electron Phonon Scattering

Under conditions of extremely high current densities, deviations from the linear current (I) – voltage (V) relation (Ohm's law) occur in normal metals. One can obtain sufficiently high current densities (of the order of 1010 A/cm2) by applying a voltage to a point contact. The nonlinear Boltzmann equation relates the nonlinearities to the energy dependence of the electron scattering probabilities. It is shown, for example, that d2V/dI2 is proportional to α2(ω)F(ω), where F(ω) is the phonon density of states and α(ω) is the electron–phonon scattering matrix element. In addition other interactions arc studied by this method such as electron–magnon interaction and the interaction of electrons with paramagnetic impurities, the well-known Kondo effect. A double point contact geometry is described which allows electron–surface scattering to be studied.

Transport properties of the ferromagnetic metals. II. Nickel

1976 ◽  
Vol 54 (1) ◽  
pp. 92-102 ◽  
Author(s):  
M. J. Laubitz ◽  
T. Matsumura ◽  
P. J. Kelly
Keyword(s):  
Transport Properties ◽  
Electron Scattering ◽  
Phonon Scattering ◽  
Positive Slope ◽  
Ferromagnetic Metals ◽  
Subsequent Publication ◽  
Consistent Group ◽  
Characteristic Features ◽  
Normal Electron ◽  
Electron Phonon Scattering

We present new experimental results for the transport properties of Ni. In comparing these results to previously published values, we show that there exists a consistent group of experimental data which establishes reliably the transport properties of pure Ni from perhaps 30 to 1500 K. In the paramagnetic range (T > 630 K), these properties show three characteristic features: a positive slope of the thermal conductivity (which is equivalent to an electrical resistivity increasing less than linearly with temperature), a large negative thermopower, and a Lorenz function substantially larger than the Sommerfeld value, L0. In attempting to provide an explanation of these features, we have discovered that the model of Mott, wherein the electronic relaxation time is inversely proportional to the density of states, does not appear to be universally valid and, more importantly, that the observed properties cannot be consistently explained if we assume pure electron–phonon scattering. To achieve consistency, at least one other scattering mechanism has to be included, such as normal electron–electron scattering; this will be taken up in detail in a subsequent publication.

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