Figure 1

Schematic of the optimal CEB with capacitive coupling to the antenna [13]. A normal nanoabsorber is coupled to the antenna through the capacitance of an SIN tunnel junction and through an SN Andreev contact. The SIN tunnel junction is also used for thermal isolation, electron cooling and for reading the signal with a SQUID or a JFET. The optical power load is relatively low: P₀ = 0.02 fW. The photon noise is$NE{P}_{\text{phot}}=\sqrt{2P_0*hf}$ _. For the 7 THz channel,$NE{P}_{\text{phot}}=4\times {10}^{-19}{\text{WHz}}^{-1/2}$.