%0 Book Section %T A 1.5 THz hot-electron bolometer mixer operated by a planar diode-based local oscillator %A Tong, C-Y Edward %A Meledin, Denis %A Blundell, Raymond %A Erickson, Neal %A Kawamura, Jonathan %A Mehdi, Imran %A Gol'tsman, Gregory %B Proc. 14[super:th] Int. Symp. Space Terahertz Technol. %D 2003 %F Tong_etal2003 %O exported from refbase (https://db.rplab.ru/refbase/show.php?record=1501), last updated on Tue, 18 May 2021 17:59:15 -0500 %X We describe a 1.5 THz heterodyne receiver based on a superconductin g hot-electron bolometer mixer, which is pumped by an all-solid-state local oscillator chain. The bolometer is fabricated from a 3.5 nm-thick niobium nitride film deposited on a quartz substrate with a 200 nm-thick magnesium oxide buffer layer. The bolometer measures 0.15 fun in width and 1.5 1..tm in length. The chip consisting of the bolometer and mixer circuitry is incorporated in a fixed-tuned waveguide mixer block with a corru g ated feed horn. The local oscillator unit comprises of a cascade of four planar doublers followin g a MMIC-based W-band power amplifier. The local oscillator is coupled to the mixer using a Martin-Puplett interferometer. The local oscillator output power needed for optimal receiver performance is approximately 1 to 2 11W, and the chain is able to provide this power at a number of frequency points between 1.45 and 1.56 THz. By terminating the rf input with room temperature and 77 K loads, a Y-factor of 1.11 (DSB) has been measured at a local oscillator frequency of 1.476 THz at 3 GHz intermediate frequency. %K waveguide NbN HEB mixers %U https://www.nrao.edu/meetings/isstt/2003.shtml %P 286