A 200 GHz CVD graphene FET based resistive subharmonic mixer

Abstract

We report on the design and characterization of a 200 GHz resistive subharmonic mixer based on a single, multichannel CVD graphene field effect transistor (G-FET). The device has gate length 0.5 µm and width 2x40 µm. The integrated mixer circuit is implemented in coplanar waveguide (CPW) technology and realized on a 100 µm thick high resistive silicon substrate. The measured mixer conversion loss (CL) is 34 ± 3 dB across 190-210 GHz band with 10 dBm local oscillator (LO) pumping power and the overall minimum CL gives 31.5 dB at 190 GHz.

A 185–215-GHz Subharmonic Resistive Graphene FET Integrated Mixer on Silicon

“…In addition, ∼30% larger RF bandwidth is achieved due to the wider stopband of the RF stub filter. This result directly demonstrates the improved mixer performance in this paper compared with that in [23].…”

“…8 shows an overall minimum CL of 27.5 dB at 192.5 GHz. The result for our previous mixer [23] is presented in Fig. 9 for comparison.…”

“…Moreover, a more thorough characterization is presented: RF and IF frequency sweeps, LO power and gate bias dependences, port isolations, and return loss. The measurements yield a record CL for graphene-based mixers of 29 ± 2 dB in the 185-210-GHz band, which is 5 dB less than [23]. The performance of our G-FET mixer on silicon is inferior to both GaAs HEMT [24] and CMOS [25].…”

“…The results in this paper represent an optimized design of the mixer circuit presented in [23]. Metalized airbridges are added to the updated mixer circuit to balance the potentials of the ground planes as well as to ensure single-mode wave propagation at the circuit T-junctions.…”

Terahertz detection using mechanical resonators based on 2D materials

“…Ultra-low-noise. coherent receiver operation of graphene at THz is largely unexplored, albeit graphene based integrated subharmonic mixer circuits have been demonstrated at 200-300 GHz frequencies [17,18].…”