|Abstract: ||The present invention is directed to the integration of a quantum cascade
laser with a hollow waveguide on a chip to improve both the beam pattern
and manufacturability. By coupling the QCL output into a single-mode
rectangular waveguide the radiation mode structure can be known and the
propagation, manipulation, and broadcast of the QCL radiation can then be
entirely controlled by well-established rectangular waveguide techniques.
By controlling the impedance of the interface, enhanced functions, such
as creating amplifiers, efficient coupling to external cavities, and
increasing power output from metal-metal THz QCLs, are also enabled.