Superconducting Integrated Submillimeter Receiver for TELIS

Abstract

In this report an overview of the results on the development of a single-chip superconducting integrated receiver for the Terahertz Limb Sounder (TELIS) balloon project intended to measure a variety of stratosphere trace gases is presented. The Superconducting Integrated Receiver (SIR) comprises in one chip a planar antenna integrated with a superconductor-insulator-superconductor (SIS) mixer, a superconducting Flux Flow Oscillator (FFO) acting as Local Oscillator (LO) and a second SIS harmonic mixer (HM) for FFO phase locking. As a result of the FFO design optimization a free-running linewidth between 9 and 1.5 MHz has been measured in the frequency range 500-710 GHz resulting in phase-locking of 35 to 95% of the FFO power correspond- ingly. A new generation of the SIR devices with improved FFO performance and optimized interface between FFO and SIS/HM has been developed and comprehensively tested. As a result all required TELIS parameters were demonstrated. Phase-locked FFO operation over entire SIR channel frequency range has been realized, spectral resolution below 1 MHz has been confirmed by gas cell and CW signal measurements. An uncorrected double side band (DSB) noise temperature below 250 K has been measured with the phase-locked FFO. The intermediate frequency bandwidth 4-8 GHz has been realized. To ensure remote operation of the phase-locked SIR several procedures for its automatic computer control have been developed and tested.Index Terms-Phase-locked oscillators, submillimeter wave integrated receivers, superconducting integrated circuits.

Stratospheric isotopic water profiles from a single submillimeter limb scan by TELIS

“…This chip is developed in collaboration with Institute of Radio Engineering and Electronics (IREE), Moscow, and is a major step in the miniaturisation of submillimeter receiver systems. For details we refer to Hoogeveen et al (2005); Koshelets et al (2007).…”

“…The calculated line profiles show small discrepancies with the actual line profiles. To account for this, the empirical Liebe model for the continuum is adopted (Liebe, 1989).…”

“…Although this explanation has been accepted as the general dehydration process of incoming tropospheric air, the actual mechanisms and locations of the influx have been subject of discussions ever since, and are still not fully resolved (Rosenlof, 2003). Several mechanisms of dehydration have been recognised; convective overshooting (Sherwood and Dessler, 2000), gradual dehydration (Holton and Gettelman, 2001), and ice lofting (Danielsen, 1982;Moyer et al, 1996;Smith et al, 2006). The reaction constants of the various processes differ for different water isotopologues, and therefore, the isotope ratios of water will provide additional insight in the different pathways of dehydration of tropospheric air.…”

“…This water is enriched in the rare, heavy isotopes with respect to water transported from the troposphere. As oxidation becomes more important for higher altitudes, this leads to an enrichment of rare isotopes with altitude (Moyer et al, 1996;Johnson et al, 2001;Ridal et al, 2001;Zahn et al, 2006).…”

Performance Assessment of Balloon-Borne Trace Gas Sounding with the Terahertz Channel of TELIS

“…Detailed information about the sensor design and the measurement capabilities of the TELIS 480-650 GHz channel can be found in [31,[34][35][36][37]. A feasibility study of isotopic water retrievals using synthetic TELIS data and the first results of hydrogen chloride (HCl) and chlorine monoxide (ClO) using real data during the 2010 campaign were presented in [38,39], respectively.…”