Patent ID: 7550734

Claim:
An integrated heterodyne terahertz transceiver, comprising: a quantum cascade laser, comprising a substrate providing a bottom waveguide layer, a plurality of layered heterostructures of two or more semiconductor alloys on the substrate, a top waveguide layer on the layered semiconductor heterostructures, thereby providing an active semiconductor core between the top and bottom waveguide layers; and at least one receiver formed in a hole in the top waveguide layer of the quantum cascade laser, comprising a rectifying metal contact on the top surface of the layered semiconductor heterostructures exposed by the hole, thereby forming a metal-to-semiconductor Schottky diode, and an antenna or horn connected to the rectifying metal contact for receiving a terahertz signal; wherein the quantum cascade laser couples terahertz local oscillator power to the Schottky diode to mix with the received terahertz signal to provide an intermediate frequency output signal.