engleski

Generation of the coherent pulses by the CDW-motion. Solutions of the microscopic model equations.

The collective transport of charge density waves (CDW) converts into an ordinary current at the contacts with a normal metal. In the present work this conversion is proposed to proceed via the process of phase slippage (PS). The CDW in the quasi-one-dimensional system with a nested Fermi surface and impurities is described by the nonlinear differential equation derived earlier. This equation is solved numerically for semi-infinite samples, as well as for finite samples with both edges fixed. The analysis of solutions is carried out for electrical fields E and sample lengths L which are respectively one to two orders of magnitude larger and smaller than the actual experimental values. This leads to the following results: the PS solutions are one-periodic functions of time, with the distance of the PS centre from the fixed end behaving like E/sup -2.84/ in the limit of small E. The coherent CDW transport in the finite samples occurs above the threshold field which varies as L/sup -1.23/. The pulses in the voltage generated by PS processes are also analysed. The results are in a good agreement with the experimental data for the length dependence of the threshold field and with some properties of the periodic noise in, for example, NbSe/sub 3/ and TaS/sub 3/.

quasione dimensional system; coherent pulses; microscopic model equations; collective transport

nije evidentirano