A Frequency Selective Surface based focal plane receiver for the OLIMPO balloon-borne telescope

摘要

We describe here a focal plane array of Cold-Electron Bolometer (CEB)detectors integrated in a Frequency Selective Surface (FSS) for the 350 GHzdetection band of the OLIMPO balloon-borne telescope. In our architecture, thetwo terminal CEB has been integrated in the periodic unit cell of the FSSstructure and is impedance matched to the embedding impedance seen by it andprovides a resonant interaction with the incident sub-mm radiation. Thedetector array has been designed to operate in background noise limitedcondition for incident powers of 20 pW to 80 pW, making it possible to use thesame pixel in both photometric and spectrometric configurations. We presenthigh frequency and dc simulations of our system, together with fabricationdetails. The frequency response of the FSS array, optical response measurementswith hot/cold load in front of optical window and with variable temperatureblack body source inside cryostat are presented. A comparison of the opticalresponse to the CEB model and estimations of Noise Equivalent power (NEP) isalso presented.