Skip to Main Content
Your organization might have access to this article on the publisher's site. To check, click on this link:http://dx.doi.org/+10.1063/1.3304783
We describe a heterogeneous terahertz (THz) quantum cascade laser that is composed of two different active region designs. This device emits simultaneously at around 2.5 and 2.9 THz with certain frequency tunability by applied current. We also investigate the spectral gain in the structure by THz time-domain spectroscopy and correlate the gain spectral bandwidth with the alignment and wavelength emission behavior of the two stack device.