Correlation between Linewidth Rin Enhancement in Semiconductor Lasers

This excellent mixer performance is due to the high device cutoff frequency as well as sharp device turn-on characteristics. The 2.4dB conversion gain achieved at W band is the result of the extremely high device cutoff frequency of 200GHz. Previous reported results for a monolithic W-band mixer using lattice matched InGaAs HEMTs with a cutoff frequency of lOOGHz had a conversion loss of 13.5dB with -6,OdBm LO drive.’ The low LO drive requirement of 3dBm reported here is the result of the extremely sharp turn-on characteristics of these devices. In conclusion, we have fabricated 0.15pm T-gate latticematched InAIAs/InGaAs/InP HEMTs with state of the art W-band performance. We have measured a device minimum noise figure of 1.7 dB with 7.7 dB associated gain. A maximum fT of 200GHr was obtained, and the 12.2dB small signal gain measured at 94GHr yielded an extrapolatedfm,,, of 380GHz. A single-ended active mixer was fabricated, and demonstrated the first reported conversion gain at W band.