title: Characterization of zero-bias microwave diode power detectors at cryogenic temperature.
abstract: We present the characterization of commercial tunnel diode low-level microwave power detectors at room and cryogenic temperatures. The sensitivity as well as the output voltage noise of the tunnel diodes is measured as functions of the applied microwave power. We highlight strong variations of the diode characteristics when the applied microwave power is higher than a few microwatts. For a diode operating at 4 K, the differential gain increases from 1000 V/W to about 4500 V/W when the power passes from -30 dBm to -20 dBm. The diode white noise floor is equivalent to a Noise Equivalent Power of 0.8 pW/Hz and 8 pW/Hz at 4 K and 300 K, respectively. Its flicker noise is equivalent to a relative amplitude noise power spectral density Sα(1 Hz) = - 120 dB/Hz at 4 K. Flicker noise is 10 dB higher at room temperature.
authors: Time and Frequency Department, CNRS FEMTO-ST Institute (UMR 6174), 26 Chemin de l'Epitaphe, 25030 Besançon, France.
authors: Vincent
authors: V
authors: Giordano
authors: Time and Frequency Department, CNRS FEMTO-ST Institute (UMR 6174), 26 Chemin de l'Epitaphe, 25030 Besançon, France.
authors: Christophe
authors: C
authors: Fluhr
authors: FEMTO Engineering, 32 Avenue de l'Observatoire 25000 Besançon, France.
authors: Benoît
authors: B
authors: Dubois
authors: Time and Frequency Department, CNRS FEMTO-ST Institute (UMR 6174), 26 Chemin de l'Epitaphe, 25030 Besançon, France.
authors: Enrico
authors: E
authors: Rubiola