Oral Presentation

Investigation of Hot Electron Bolometer Mixer using Magnetic Thin Film

Author(s): Akira Kawakami, Yoshihisa Irimajiri, Taro Yamashita, Satoshi Ochiai, Yoshinori Uzawa

Presenter: Akira Kawakami (National Institute of Information and Communications Technology)

To increase the IF bandwidth and improve the sensitivity of hot electron bolometer mixer (HEBM), we examined a new HEBM structure using a magnetic Ni thin film. We found that it is possible to suppress the superconductivity of the NbN(5 nm) layer by the deposition of a Ni(1.8 nm) thin film,. It was also confirmed that the superconductivity disappeared in the Au(100 nm)/Ni(1.8 nm)/NbN(5 nm) multilayer forming the electrodes of the HEBM. By using the electrode, we thought that hot spots are formed near the electrodes and it is effective for shortening the relaxation time of hot electrons. The HEBMs using Ni thin film were fabricated and evaluated the IF bandwidth at 1.9 THz. We confirmed that the IF bandwidth expands, and the evaluated bandwidth was about 5.7 GHz.