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O. Yu. Titov

Publications and source records attributed to O. Yu. Titov.

8 recordsLinked to original sources
arXiv2004

Recombination and Lifetimes of Charge Carriers in Semiconductors

In this Communication, it is shown that models used for describing generation and recombination of electrons and holes lead to disagreements with Maxwell's electrodynamics. Self-consistent expressions, more adequately depicting the actual physical processes of electron-hole recombination in semiconductors are obtained. It is shown that the electron and hole lifetimes can be defined correctly only for the special cases when the electron and hole nonequilibrium concentrations are the same, these lifetimes being equal. The influence of temperature inhomogeneity on the recombination is also considered. The recombination rate for hot electrons is obtained in the case when the electron and hole temperatures differ.

cond-mat.soft↗
arXiv2002

The Role of Non-Equilibrium Carriers in Formation of Thermo-E.M.F. in Bipolar Semiconductors

A new approach to thermoelectric phenomena, as a linear transport process of non-equilibrium charge carriers, is presented. The role of non-equilibrium carriers, as well as surface and bulk recombination, is demonstrated to be crucial even within a linear approximation. Electron and hole Fermi quasi-levels appeared in a thermal field are calculated in the case of thermoelectric current flow through a circuit. It is shown, for the first time, that the Fermi quasi-level of one of subsystem of quasi-particles can be a non-monotonic function of the coordinates. General expressions for the thermoelectric current, thermo-e.m.f., and electrical resistance of bipolar semiconductors have been obtained. For the first time the surface recombination and surface resistance were taken into account.

cond-mat↗
arXiv2002

New physical principles of contact thermoelectric cooling

We suggest a new approach to the theory of the contact thermoelectric cooling (Peltier effect). The metal-metal, metal-n-type semiconductor, metal-p-type semiconductor, p-n junction contacts are analyzed. Both degenerate and non-degenerate electron and hole gases are considered. The role of recombination in the contact cooling effect is discussed by the first time.

cond-mat↗
arXiv2002

Boundary Conditions in an Electric Current Contact

In most electronic devices, electric current of both types (electrons and holes) flows through a junction. Usually the boundary conditions have been formulated exclusively for open circuit. The boundary conditions proposed here bypass this limitation by the first time, as far as we are aware. Besides, these new boundary conditions correctly describe current flow in a circuit, i.e., closed circuit conditions, which are the usual operation conditions for electronic devices and for the measurement of many transport properties. We also have generalized the case (as much as it is possible in a classical treatment), so self-consistent boundary conditions to describe current-flow through a contact between two arbitrary conducting media are developed in the present work. These boundary conditions take into account a recently developed theory: influence of temperature space inhomogeneity due to the interfaces and quasi-particles temperature-mismatch on thermo-generation and recombination. They also take into account surface resistance, surface recombination rates and possible temperature discontinuities at the interface due to finite surface thermo-conductivity. The temperature difference between current-carriers and phonon subsystems is also included in this approach.

cond-mat.mtrl-sci↗
arXiv1997

Spatially nonuniform energy distribution of electrons in a submicron semiconductor film

The symmetric part of the distribution of the electrons in a semiconductor submicron film, placed between a heater and refrigeration unit, is derived and analyzed. It is shown that, in general, it is of non-Fermi (non-Maxwellian) nature. A new mechanism is proposed to account for the non-Maxwellian form of the symmetric part of the distribution function. This mechanism is based on the different energy dependences of the momentum relaxation time in the bulk of the semiconductor and its skin layer.

cond-mat↗
arXiv1997

Theory of thermoelectric effects when the temperature approximation is incorrect

The flow of a thermoelectric current through a semiconductor of submicron dimensions is analyzed. The rate of surface relaxation of the energy is assumed to be much higher than the rate of electron-electron collisions. Under these conditions, it is incorrect to describe the electron gas by means of a Maxwellian distribution and thus to describe the thermoelectric effects in terms of an electron temperature and a chemical potential. A theory is derived for these effects. This theory does not include the latter parameters and is based on a non-Maxwellian distribution which is spatially nonuniform in terms of energy.

cond-mat↗
arXiv1995

The Nature of Thermopower in Bipolar Semiconductors

The thermoemf in bipolar semiconductors is calculated. It is shown that it is necessary to take into account the nonequilibrium distribution of electron and hole concentrations (Fermi quasilevels of the electrons and holes). We find that electron and hole electric conductivities of contacts of semiconductor samples with connecting wires make a substantial contribution to thermoemf.

cond-mat↗