  The paper overviews experimental and theoretical studies of photogalvanic
effects induced in BiSbTe- based three dimensional topological insulators by
polarized terahertz radiation. We present the state-of-the-art of this subject,
including most recent and well-established results. We discuss a
phenomenological theory based on symmetry arguments and models illustrating the
photocurrents origin. We give a brief glimpse of the underlying microscopic
theory, as well as an overview of the main experimental results.
