Infrared laser emission at a number of wavelengths between 9.4 &mgr; and 13.7 &mgr; has been obtained from diodes of Pb1−ySnySe and Pb1−xSnxTe at 12°K and 77°K. Diodes were fabricated from vapor‐grown Pb1−ySnySe and both vapor‐grown and Bridgman‐grown Pb1−xSnxTe. Emission data indicate that, as in Pb1−xSnxTe, the energy gap in Pb1−ySnySe decreases with increasing Sn concentration, becoming zero at 12°K for some value ofywithin the range 0.11 ≤y≤ 0.14.