We show that clusters of galaxies induce steplike wiggles on top of the cos
mic microwave background (CMB). The direction of the wiggle is parallel to
the large-scale gradient of the CMB, allowing one to isolate the effect fro
m other small-scale fluctuations. The effect is sensitive to the deflection
angle rather than its derivative (shear or magnification) and thus traces
outer parts of the cluster with higher sensitivity than some other methods.
A typical amplitude of the effect is 10 mu K(sigma(v)/1400 km s(-1))(2), w
here sigma(v) is the velocity dispersion of the cluster, and several mu K s
ignals extend out to a fraction of a degree. We derive the expressions for
the temperature profile for several simple parameterized cluster models and
identify some degeneracies between parameters. Finally, we discuss how to
separate this signal from other imprints on the CMB using custom-designed f
ilters. Detection of this effect is within reach of the next generation of
small-scale CMB telescopes and could provide information about the cluster
density profile beyond the virial radius.