A low noise 410-495 heterodyne two tuner mixer, using submicron Nb/Al2O3/Nb tunneljunctions

A 410-495 GHz heterodyne receiver, with an array of two Nb/Al2O3/Nb tunneljunctions as mixing element is described. The noise temperature of this receiver is below 230 K (DSB) over the whole frequency range, and has lowest values of 160 K in the 435-460 GHz range. The calculated DSB mixergain over the whole frequency range varies from -11.9 plus or minus 0.6 dB to -12.6 plus or minus 0.6 dB and the mixer noise is 90 plus or minus 30 K

to H. L. Erlicher re: carboloy application in metal working industry.--Correspondence

to H. L. Erlicher re: carboloy application in metal working industry

DC heating in SIS tunnel devices for THz mixing applications.

Heating effects in Superconductor- Insulator- Superconductor (SIS) tunnel junctions are studied by comparing SIS junctions equipped with niobium and aluminum electrodes. A temperature rise of several K is observed with niobium, which is reduced by an order of magnitude with aluminum. A simple model satisfactorily explains this observation and predicts an increase in the noise temperature of up to 30% at the operating voltage for heterodyne mixing due to this effect

ASUR - AN AIRBORNE SIS RECEIVER FOR ATMOSPHERIC MEASUREMENTS OF TRACE GASES AT 625 TO 760 GHZ

A heterodyne receiver making use of a SIS waveguide mixer with integrated horn and single backshort tuner has been built, It has been used for a series of airborne measurements of atmospheric trace gases, such as HCl and ClO, above northern Europe during the winter of 1993 and 1994. The receiver is suitable for measurements in the range of 625-760 GHz and shows stable operation in the airplane together with high sensitivity. Best achieved noise temperatures are T-DSB = 310 K at 708 GHz in the laboratory and T-SSB = 1500 K at 625 GHz for the complete system in the airplane