K Sigfrid Yngvesson

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Based on the excellent performance of NbN HEB mixer receivers at THz frequencies which we have established in the laboratory, we are building a Terahertz REceiver with NbN HEB Device (TREND) to be installed on the 1.7 meter diameter AST/RO submillimeter wave telescope at the Amundsen/Scott South Pole Station. TREND is scheduled for deployment during the(More)
The effect of microwave power magnitude and pulsing frequency on the synthesis enhancement of zeolites, silicoaluminophosphate SAPO-11, silicalite, and NaY, was studied. Pulsing the microwave power compared to continuous delivery at the same averaged fed microwave power showed no effect on the nucleation and crystallization rates of SAPO-11, silicalite, or(More)
In this paper, we first review general quantum mechanical limits on the sensitivity of heterodyne receivers. The main aim of the paper is to explore the quantum-noise (QN) properties of hot electron bolometric (HEB) mixers. HEB mixers have a characteristic feature not found in other mixers: based on the "hot-spot" model, the conversion loss varies along the(More)
We present measurement results for a new type of integrated terahertz receiver, as an extension to previous work by the authors. The receiver we developed integrates quasi-optically coupled phonon-cooled NbN hot electron bolometric (HEB) mixers in close proximity with InP monolithic microwave integrated circuit (MMIC) intermediate-frequency (IF) amplifiers.(More)
We report on the development and characterization of a passive heterodyne hot electron bolometer (HEB) imager operating at 850 GHz. HEB detectors provide unprecedented sensitivity and spectral resolution at terahertz frequencies covering the frequency range of 0.5-5 THz. Terahertz imagers based on HEB technology have sufficient sensitivity to operate in a(More)
Studies in the last decade suggest that microwave energy may have a unique ability to influence chemical processes. These include chemical and materials syntheses as well as separations. Specifically, recent studies have documented a significantly reduced time for fabricating zeolites, mixed oxide and mesoporous molecular sieves by employing microwave(More)
This paper presents a detailed study of the IF properties of phonon-cooled NbN hot electron bolometer (HEB) terahertz mixers and receivers, performed over the widest intermediate frequency range reported so far. First, a broadband technique is used to obtain the IF small-signal output impedance of HEB mixers using network analyzer measurements. The(More)