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Light bottle generated by Bragg volume grating

Structured light beams have useful attributes to different scientific, industrial and technological applications. Of particular interest are light distributions containing well-defined dark regions. Such distributions are usually called - dark beams, black beams, "doughnut" mode and light bottles and have widely known applications in optical metrology and atom physics. The conventional way to generate these distributions is by various diffractive optical elements and also by special laser cavity design. In this paper we present a simple method, which is based on the Bragg selectivity of volume gratings. Initial experimental results show promising potentials of such approach.