Dynamic behavior of a piezowalker, inertial and frictional configurations

We have examined two configurations of a piezowalker, the inertial and the frictional one, both of which are capable of moving samples with submicrome ter steps over a distance of some millimeters. We demonstrated that, contra ry to expectations, operation of the frictional walker in which six piezos shear one by one, is still dependent on inertial slip-stick action. We stud ied the dependence of the step size on the time delay between rising fronts applied to consecutive piezos and we found that the characteristic time as sociated with the minimum value of the step size is of the order of the tim e of a sound wave propagating along the rod between the piezos. (C) 1999 Am erican Institute of Physics. [S0034-6748(99)04609-2].