  Structure of confining string in terms of the topological charge density and
the action density is studied in SU(2) Yang-Mills theory on the lattice using
HP1 sigma-model embedding approach. We find that the confining flux tube
noticeably suppresses both the topological charge and the action densities.
Beyond the string formation length the string cross section in terms of these
quantities is well described by a Gaussian profile. In both cases the squared
string width is found to be a logarithmic function of the string length
confirming the Luscher widening of the chromoelectric string. Characteristic
string scales in terms of the topological and action densities are estimated as
well.
