Fig. 16: Emission spectra of the lasers measured at 300 K at a current density of 400 A cm−2 (∼0.5 Jth) and above the threshold (black lines).
From: Mid-infrared III–V semiconductor lasers epitaxially grown on Si substrates
a QCL grown on a native InAs substrate, b QCL grown on a Si substrate. Red curves show Lorentzian fits of the spectra. Reprinted from ref. 34, used in accordance with the Creative Commons Attribution (CC BY) license
