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We report the growth and fabrication of midwave infrared InAs/GaSb strain layer superlattice (SLS) detectors. Growth of alternate interfaces leads to a reduced strain between the GaSb buffer and SLS (Δa∥/a=-5×10-4), enabling the growth of active regions up to 3 μm (625 periods). The structural, optical, and electrical properties of the active region were characterized using x-ray crystallography and photoluminescence, respectively. p-i-n detectors were grown using 625 periods of 8 ML (monolayer) InAs/8 ML GaSb as the active region. The λcutoff for the detectors was 4.6 μm with a conversion efficiency of 32% at Vb=-0.2 V. Detectivity was obtained using noise power spectral density measurements under 300 K 2π field of view illumination and was equal to 5.2×1010 and 3×1010 cm Hz1/2/W (Vb=-0.02 V, T=80 K) in the white noise and 1/f noise limit (at 50 Hz). [ABSTRACT FROM AUTHOR]