P.I. Baranskii. On the importance of basic theory of thermoelectricity for scientific and technical progress. Journal of
Thermoelectricity. 2006, No.3. - p.7-13.
“The subject matter of anisotropic scattering theory is to develop a method for solving a kinetic equa-tion under anisotropic scattering conditions. And it is not a question of some mathematical refinement of standard kinetic theory of semiconductors, but solving matters of principle.” (
A.G.Samoilovich).
V.V. Chernysh. A.G. Samoilovich and investigations of transport phenomena in elastically deformed germanium Journal of
Thermoelectricity. 2006, No.3. - p.14-24.
Brief analysis of the works by Prof. A.G. Samoilovich and his students was performed for the inves-tigation of transport phenomena in elastically deformed germanium. Piezoresistance in electronic germanium (L1 - Delta1-germanium model) which is uniaxially deformed along [001] is examined. The comparison of known experimental data with the obtained theoretical results enabled us to specify the values of effective masses and deformation potentials in Delta1- valleys of germanium.
Yu.G. Gurevich, G.N.Logvinov. Theory of thermoelectric cooling in isotropic semiconductors (Review). Journal of
Thermoelectricity. 2006, No.3. - p.25-45.
A new approach is suggested to explain the Peltier effect. This approach is based on the idea of occur-rence of induced thermal diffusion fluxes in any nonuniform medium through which a d.c. electric cur-rent passes, in particular in a structure composed of two different uniform semiconductors. These in-duced thermal diffusion fluxes tend to compensate the change in the thermal fluxes carried by an elec-tric current (drift thermal fluxes) in their passage through the junction in accordance with the general Le Chatelier-Braun principle. The occurrence of these thermal diffusion fluxes leads to temperature nonuniformity in the structure and, as a result, to junction cooling or heating.
The general heat balance equations are derived. It is shown that only two bulk sources of heat occur. These are the Joule source of heat and the Thomson source of heat. Both are commensurable in their intensity in the problem under study. There is no Peltier source of heating or cooling in the bulk.
A new equation for the Thomson heat is derived and its physical interpretation is given.
The general boundary conditions for the heat balance equation are derived. Analysis of these boundary conditions shows that no Peltier sources of heat are present at the junctions either. It is shown that in the general case the thermoelectric cooling is a superposition of two effects, the isothermal Peltier effect and the adiabatic Peltier effect. Both are essentially dependent on the junction surface thermal conductivity. The isothermal Peltier effect is maximum at large values of surface thermal conductivity and disappears in case when junction thermal conductivity is sufficiently low. The adiabatic Peltier ef-fect is most pronounced in the case of low surface thermal conductivity values, at large values thereof it is negligibly small.
Dependence of thermoelectric cooling (heating) on the geometrical dimensions of the structure is dis-cussed.
It is shown that thermoelectric cooling (heating) is a thermodynamically reversible process as a linear approximation with regard to applied electric current.
L.P. Bulat. Anisotropy of scattering potential in semiconductors and anisotropic scattering theory. Journal of
Thermoelectricity. 2006, No.3. - p.46-50.
Basic results related to research on the influence of anisotropy of piezoelectric potential on transfer phenomena in semiconductors with the zinc blende and wurtzite structure are reported.
P.M.Gorley, Yu.V.Vorobiev, J.Gonzalez-Hernandez, P.P.Gorley, Î.Î. Galochkina. Influence of nonparabolicity of the law of carrier energy dispersion on thermoEMF in wurtzite-structure crystals. Journal of
Thermoelectricity. 2006, No.3. - p.51-56.
The paper gives the results of research on the influence of a term linear in wave vector k in the law of carrier energy dispersion E(k) on the value and character of thermoEMF dependence on the temperature and type of dominant scattering mechanisms for crystals with wurtzite structure. Theoretical studies were performed for cases of strongly degenerate and nondegenerate statistics of electron gas in the relaxation time approximation, taking into account scattering of carriers on impurity ions, acoustic and optical vibrations of crystal lattice (the latter – for temperatures essentially higher and lower than the Debye temperature ThetaD). It is shown that in high-temperature region the presence in E(k) of a term linear in k leads to increased degree of carrier gas nondegener-acy, shifting the Fermi level deep into the energy gap, that can essentially affect the value and character of temperature dependence of thermoEMF tensor components. In so doing, anisotropy of thermoEMF tensor components is determined by the type of dominant carrier scattering mechanisms and can be found experimentally.
À.À. Snarskii, M.I. Zhenirovskii, I.V. Bezsudnov. On the Wiedemann-Franz law in thermoelectric composites. Journal of
Thermoelectricity. 2006, No.3. - p.57-63.
Theoretical analysis of the effect of thermoelectric phenomena on the relation of effective electrical and thermal conductivity in the macroscopically inhomogeneous media is carried out. Plane-layered structures, two-dimensional self-dual and three-dimensional randomly inhomogeneous media are examined. It is shown that the relation of effective electrical to thermal conductivity, which is inde-pendent of concentration in so-called Wiedemann –Franz media, in the case of high values of inter-nal thermoelectric figure of merit can be considerably different from the one for the local values in each phase. The decrease of the relation may have negative impact on the effective figure of merit of composites and thus lead to the decrease of thermoelectric devices efficiency.
L.I. Anatychuk, L.N. Vikhor, V.V. Malyshko, V.A. Nekhai. Cooling modules of segmented thermoelements. Journal of
Thermoelectricity. 2006, No.3. - p.64-71.
The methods of optimal control theory are used for the development of a technique for a compute¬rized design of cooling modules of segmented thermoelements under maximum coefficient of per-formance. The possibility of increasing maximum coefficient of performance of such modules is in-vestigated.
An example of module design of double-segmented legs is given with comparison of calculated power characteristics of module to their experimentally measured results obtained on module sam-ples elaborated using the proposed design method.
À.À. Ascheulov. On coordinate sensitivity of anisotropic opticothermoelements with longitudinal thermoEMF. Journal of
Thermoelectricity. 2006, No.3. - p.72-74.
Results of experimental research on coordinate sensitivity of anisotropic opticothermoelement are presented. Bright outlook for its use as a modulation-free coordinate-sensitive nonselective array to determine the density of radiant fluxes in wide spectral and dynamic ranges is demonstrated.
L.I. Anatychuk, V.Ya. Mikhailovsky, O.J. Luste, O.Yu. Baglai. Thermoelectric generators for powering automated gas heaters. Journal of
Thermoelectricity. 2006, No.3. - p.75-85.
The results of investigation and development of thermoelectric generators for powering safety automated systems of gas heaters are presented. It is demonstrated that response speed of thermogenerators built using two-stage design is 1.5-2 times superior to response speed of all known counterparts. The design of such thermoelectric generator is given.
A.M. Gnatiuk, R.V. Kuz. Eddy zone-inhomogeneous thermoelement. Journal of
Thermoelectricity. 2006, No.3. - p.86-94.
Spiral zone-inhomogeneous thermoelement is prepared and experimentally investigated in the electrical power generation mode. The calculations of its parameters performed using computer-based model in the previous researches are validated. The reliability of zone-inhomogeneous thermoelement with passive redundancy is determined. The advantages of spiral zone- inhomogeneous thermoelement in comparison with thermocouple element are shown.
A.V. Prybyla. Efficiency of spiral rectangular anisotropic thermoelement with regard to temperature dependence of kinetic coefficients. Journal of
Thermoelectricity. 2006, No.3. - p.95-102.
The computer-based model of spiral rectangular anisotropic thermoelement (SRAT) is developed. The model makes possible the investigation of physical fields distributions in thermoelement with regard to temperature dependences of material kinetic coefficients. The difference in the potential and current distribution in spiral anisotropic thermoelement is shown taking into account these temperature dependencies and disregarding them.