Title :
Development of submillimeter-wave camera for Atacama Submillimeter Telescope Experiment
Author :
Matsuo, Hiroshi ; Ariyoshi, Seiichirou ; Akahori, Hiromichi ; Takeda, Masanori ; Noguchi, Takashi
Author_Institution :
Adv. Technol. Center, Nat. Astron. Obs., Tokyo, Japan
fDate :
3/1/2001 12:00:00 AM
Abstract :
Submillimeter-wave focal plane arrays based on superconducting direct detectors are designed to be used on a new 10-m submillimeter-wave telescope in Chile. Niobium tunnel junctions with low leakage current coupled to antenna structures can be sensitive submillimeter-wave direct detectors when high quantum efficiency and low leakage current are realized. Inhomogeneous distributed junctions coupled to log-periodic antennas can be used to realize this. Input coupling of better than 50% is calculated with a bandwidth of more than 60 GHz using low current density inhomogeneous distributed junctions. Their measured leakage current of 5 pA and their shot-noise limited operation suggests that noise equivalent power of less than 10-17 W/Hz0.5 at operating temperature of 0.9 K could be achieved
Keywords :
cameras; focal planes; niobium; submillimetre astronomy; submillimetre wave detectors; submillimetre wave imaging; superconductor-insulator-superconductor devices; 0.9 K; 5 pA; 60 GHz; Atacama Submillimeter Telescope Experiment; Nb; SIS photon detector; astronomical imaging; focal plane array; input coupling; leakage current; log-periodic antenna; niobium tunnel junction; noise equivalent power; quantum efficiency; shot noise; submillimeter wave camera; superconducting direct detector; Cameras; Detectors; Josephson junctions; Leak detection; Leakage current; Log periodic antennas; Niobium; Optical design; Sensor arrays; Telescopes;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
