Poster report [5957-49] on “Theoretical study of a graded-band-gap p-n structure with negative luminescence” by B.S. Sokolovsky, V.K. Pysarevsky, Ivan Franko National Univ. of L'viv (Ukraine) on 31 August 2005 at the SPIE conference on Optics and Optoelectronics in Warsaw (Poland).