Title :
Twin-Slot Antenna Coupled NbN Hot Electron Bolometer Mixer at 2.5 THz
Author :
Zhang, Wen ; Gao, Jian-Rong ; Hajenius, Merlijn ; Miao, Wei ; Khosropanah, Pourya ; Klapwijk, Teun M. ; Shi, Sheng-Cai
Author_Institution :
Purple Mountain Obs., Chinese Acad. of Sci., Nanjing, China
Abstract :
We demonstrate a quasi-optical NbN hot electron bolometer (HEB) mixer using a twin-slot antenna on a Si lens to couple terahertz radiation. The mixer shows a receiver noise temperature of 1150 K at 2.5 THz, which is expected based on a model that includes quantum noise. The measured direct response is understood by taking into account the main beam efficiency and the parasitic reactance due to the geometric change between bolometer and transmission line. The measured beam of the mixer is nearly collimated and has a Gaussian beam efficiency of 90% with side-lobes below -16 dB.
Keywords :
bolometers; hot carriers; mixers (circuits); niobium compounds; quantum noise; slot antennas; submillimetre wave antennas; transmission lines; Gaussian beam efficiency; HEB mixer; NbN; direct response measurement; frequency 2.5 THz; parasitic reactance; quantum noise; temperature 1150 K; terahertz radiation; transmission line; twin-slot antenna coupled hot electron bolometer mixer; Antenna measurements; Antennas; Astronomy; Bolometers; Coplanar waveguides; Mixers; Noise; Observatories; Superconducting devices; Temperature measurement; Beam pattern; direct response; hot electron bolometer; receiver noise temperature;
Journal_Title :
Terahertz Science and Technology, IEEE Transactions on
DOI :
10.1109/TTHZ.2011.2145330
