Proof of concept external ring cavity Quantum Cascade Laser

We propose to construct a new type of Quantum Cascade Laser (QCL) device, based on an
external ring cavity. External cavities have already been utilised to expand the available
tuning range of QCL devices. Indeed tuning from around 7 microns up to 11 microns has been
demonstrated from an external cavity QCL (ECQCL). In addition the use of ring cavities to
produce widely tuneable and highly stable single frequency laser light is well known (indeed
M Squared produce a state-of-art Titanium:Sapphire laser product based on such a geometry).
We propose here to leverage both of these approaches i.e. an external ring cavity, together
with M Squared’s proprietary technologies in relation to low noise drive electronics and stable
optical mounting, to produce a proof of concept ring ECQCL with state-of-the-art tuning range
across the full infrared waveband (MWIR and LWIR) combined with exemplary spectral
purity. A narrow linewidth ring QCL is an exciting platform technology which will both
enable and significantly improve applications in key areas such as environmental
sustainability, medicines and healthcare as well as defence and security. A product arising
from a successful project outcome would be an innovative system offering significantly
improved performance and functionality and be designed with inherent reliability, these
features will be combined with a intuitive user interface to provide end users with a powerful
new technology to drive new high value applications.