Cosmic string lens effects on CMB polarization patterns

Extending the Kaiser-Stebbins mechanism we propose here a method for detecting relics of topological defects such as cosmic strings based on lens-induced small-scale B-type polarization in the CMB. Models of inflation, in which large scale structures of the Universe emerge from the inflaton fluctuations,do not exclude the formation of topological defects at the end of the inflationary phase. In such case, we show that the lens effect of a string on the small scale E-type polarization of the CMB induces a significant amount of B-type polarization along the line-of-sight. The amplitude of the effect is estimated for different resolutions of CMB experiments.