Giordano Vincent, Fluhr Christophe, Dubois Benoît, Rubiola Enrico
Time and Frequency Department, CNRS FEMTO-ST Institute (UMR 6174), 26 Chemin de l'Epitaphe, 25030 Besançon, France.
FEMTO Engineering, 32 Avenue de l'Observatoire 25000 Besançon, France.
Rev Sci Instrum. 2016 Aug;87(8):084702. doi: 10.1063/1.4960087.
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.
我们展示了商用隧道二极管在室温和低温下的低电平微波功率探测器的特性。测量了隧道二极管的灵敏度以及输出电压噪声与所施加微波功率的函数关系。我们强调当所施加的微波功率高于几微瓦时，二极管特性会有显著变化。对于在4 K下工作的二极管，当功率从-30 dBm变为-20 dBm时，微分增益从1000 V/W增加到约4500 V/W。该二极管的白噪声本底在4 K和300 K时分别相当于0.8 pW/Hz和8 pW/Hz的噪声等效功率。其闪烁噪声在4 K时相当于相对幅度噪声功率谱密度Sα(1 Hz) = - 120 dB/Hz。在室温下闪烁噪声高10 dB。
