Full QO setup showing the millimetre wave head on the right and the multenna mounted in the centre of the bench. The power supply drives a power amplifier on the input chain.

Measurements of non-linear sub-THz quasi-optical devices

Rostyslav F. Dubrovka, Oleksandr Ju. Sushko, Melusine Pigeon, Peter Alizadeh, Andre Sarker Andy, Robert S. Donnan, Clive G. Parini, James W. E. Kneller, Theo Kreouzis


The paper presents recent developments in designing quasi-optical multipliers in the sub-THz frequency domain. An extensive measurement campaign is described in detail in which issues are addressed concerning the non-trivial nature of the problems met. In particular, attention is paid to impedance measurements of the core element, the integrated antenna-multiplier (dubbed the ‘multenna’), together with the associated experimental apparatus for detection of its higher-order harmonics. Finally, use of a light-sensitive semiconducting organic polymer is demonstrated as a tuneable dielectric that will enable elements of a multenna array to be phase-locked for generation of coherent emission.


sub-Terahertz; sub-THz; quasi-optical


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