Broad-stripe, single-mode, mid-IR interband cascade laser with photonic-crystal distributed-feedback grating

We have demonstrated an electrically pumped photonic-crystal distributed-feedback laser with an interband cascade active region emitting at 3.3μm. At 78K, the stripe of width 400μm emits up to 67mW of cw power into a single spectral mode with side-mode suppression ratio ≈27dB. The full width at half maximum of the far-field divergence angle is ≈0.5°, which combined with the near-field profile yields an effective M2 of 1.7–2.0.