Superlattice quantum cascade lasers operating at very long wavelengths (λ≈17 μ)

We present the realization of a quantum cascade (QC) laser employing so-called "chirped" superlattices and operating at 17 μm, which represents the first demonstration of a semiconductor injection laser based on intra-band transitions at wavelengths beyond the atmospheric windows. A schematic band diagram of the structure, which has been grown by molecular beam epitaxy (MBE) in InGaAs-InAlAs is given