Noise measurements of the low Tc MgB2 HEB mixer at 1.6THz and 2.6THz

Paper in proceeding, 2015

We present results on MgB2 hot-electron bolometer noise measurements to show reproducibility of achieved results and robustness of the fabricated devices, which being passivated with silicon nitride shows the same performance after 1.5 year storing in nitrogen atmosphere. Noise temperature measurements were performed for the HEB made of 10nm MgB2 thin film on Al2O3 with Tc of 8.5K for 1.6THz LO at 2.7K and 4.2K. The minimum double side band noise temperatures corrected for optical losses for different bath temperatures were 700K and 1150K, whereas the noise bandwidth was 3.2GHz and 3.5GHz, respectively. The mixer output noise temperature and the conversion gain were 26K and -17.7dB, 27K and -14.9dB, respectively. For 2.6THz LO at 2.7K the corresponding values are 1200K and 3.7GHz.