STATIC PROPERTIES OF CHARGE-DENSITY WAVES AT THE DEPINNING TRANSITION

We study the static properties of charge density waves, in the presence of quenched random impurities, at the depinning transition. We develop an analytical approach based on a simple assumption for the fluctuations that are compatible with a static solution; this allows us to deduce approximate equations for the threshold field, in the limit of strong pinning. These equations admit an approximate perturbative solution in any dimension, which results in an excellent agreement with the data of the simulations in the strong pinning regime, while it is qualitatively correct for weak pinning.