Quantum electrodynamics (in Russian)

V.B. Berestetskii, Лев П. Питаевский, E.M. LIFSHITZ

V.B. Berestetskii, Лев П. Питаевский, E.M. LIFSHITZ

Julian Schwinger, J. C. Polkinghorne

Мясин Константин Игоревич

In connection with volumes of the transferred information grow, the list of telecommunication services extends and at the same time increase the quality requirements. Russian operators of Uniform telecommunication network should solve the problem of increasing the throughput of existing lines. Some Russian operators have already moved to coherent detection technology in own fiber-optic transport network. However, this transition is uneconomical due to the high cost of equipment. Multilevel modulation formats include high spectral efficiency and resistance to dispersion, it is useful for increasing the transmission rate in communication systems with wavelength division multiplexing. Article presents a model of fiber-optic channel model, which allows finding the optimal location of the signal levels with multilevel modulation intensity (IM-M). The model is create according to postulates of quantum electrodynamics and has good convergence to results of known researches. This model can be a solution to many optimization problems of synthesis and analysis of fiber-optical communication lines with multilevel signals.

Kurt Haller

V. S. Olkhovsky

The formal mathematical analogy between time-dependent quantum equation for the nonrelativistic particles and time-dependent equation for the propagation of electromagnetic waves had been studied in [A. I. Akhiezer and V. B. Berestezki, Quantum Electrodynamics (FM, Moscow, 1959) [in Russian] and S. Schweber, An Introduction to Relativistic Quantum Field Theory, Chap. 5.3 (Row, Peterson & Co, Ill, 1961)]. Here, we deal with the time-dependent Schrödinger equation for nonrelativistic particles and with time-dependent Helmholtz equation for electromagnetic waves. Then, using this similarity, the tunneling and multiple internal reflections in one-dimensional (1D), two-dimensional (2D) and three-dimensional (3D) particle and photon tunneling are studied. Finally, some conclusions and future perspectives for further investigations are presented.