Interband cascade lasers with ten active stages were grown by molecular beam epitaxy (MBE). Devices emitting near 3.6 mu m at room temperature operated in pulsed mode to a temperature of 330 K. The threshold cur-rent densities were the lowest to date for NRL growths, ranging from 9 A/cm(2) at 78 K to 1.7 kA/cm(2) at 300 K. The voltage efficiency was approximate to 94% at 140 K, and the pulsed slope efficiency was 121 mW/A at 300 K. Antimonide photodetectors with a cutoff wavelength of 12 Am were also grown in the same machine by MBE. The absorbing layer consisted of an InAs/GaInSb type-II superlattice, and the depletion region comprised a four-layer "W" structure with a graded energy gap in order to minimize the tunneling and generation currents. Quantum efficiencies of 30%-40% were achieved in the 8 - 10 mu m band. (c) 2007 American Vacuum Society.