Figure 3. Generation–detection experiment with ac-biased detector junction.

(a) Temperature dependence of the equilibrium ac resistance of the mesa 4b. (b) Normalized resistances of different detector mesas at T=61 K as a function of power in the generator mesa 6a. (c) Resistance of the detector mesa 4b at T=10 K as a function of power in the generator mesa 4a. (d) dI/dV(V) characteristics of the generator mesa 4a at different T. Peaks at sum-gap voltages are clearly seen. (e,f) Normalized detector responses of mesas 4b and 2a as a function of voltage in the generator 4a at different T. Peak responses occur at the sum-gap voltages in the generator.