Three-terminal junctions operating as mixers, frequency doublers and detectors: a broad-band frequency numerical and experimental study at room temperature

The frequency response of nanometric T- and Y-shaped three-terminal junctions (TTJs) is investigated experimentally and numerically. In virtue of the parabolic down-bending of the output voltage of the central branch obtained at room temperature under a push–pull fashion input, we analyse the low-frequency performance (<1 MHz) of TTJs operating as mixers, their RF capability as doublers up to 4 GHz and detection at 94 GHz. Special attention is paid to the impedance matching and cut-off frequency of the measurement setup. The numerical study is carried out by means of Monte Carlo simulations. We illustrate the intrinsic functionality of the device as frequency doubler or rectifier up to THz. The role of the width of the central branch on the high-frequency response is also explored, finding different cut-off frequencies for doubling and detection as a consequence of the diverse working principles of both mechanisms and the particular geometry of the TTJs.