Low-noise 0.5THz all-NbN superconductor-insulator-superconductor mixer for submillimeter wave astronomy

2008 ◽  
Vol 92 (22) ◽  
pp. 222504 ◽  
Author(s):  
Jing Li ◽  
Masanori Takeda ◽  
Zhen Wang ◽  
Sheng-Cai Shi ◽  
Ji Yang
Keyword(s):  
Submillimeter Wave ◽  
Low Noise

Low-noise millimeter- and submillimeter-wave receivers

1998 ◽  
Vol 41 (11) ◽  
pp. 965-979 ◽  
Author(s):  
V. F. Vdovin ◽  
I. I. Zinchenko
Keyword(s):  
Submillimeter Wave ◽  
Low Noise ◽  
Submillimeter Wave Receivers

Superconducting RF tuning circuits for low-noise submillimeter wave SIS receivers

1994 ◽  
Author(s):  
P. Febvre ◽  
W. R. McGrath ◽  
B. Bumble ◽  
H.G. LeDuc ◽  
S. George ◽  
...  
Keyword(s):  
Submillimeter Wave ◽  
Low Noise ◽  
Superconducting Rf ◽  
Rf Tuning

scholarly journals Low-noise submillimeter-wave NbTiN superconducting tunnel junction mixers

1999 ◽  
Vol 75 (25) ◽  
pp. 4013-4015 ◽  
Author(s):  
Jonathan Kawamura ◽  
Jian Chen ◽  
David Miller ◽  
Jacob Kooi ◽  
Jonas Zmuidzinas ◽  
...  
Keyword(s):  
Tunnel Junction ◽  
Submillimeter Wave ◽  
Low Noise ◽  
Superconducting Tunnel Junction

scholarly journals Demonstration of a wideband submillimeter-wave low-noise receiver with 4–21 GHz IF output digitized by a high-speed 32 GSps ADC

2020 ◽  
Vol 640 ◽  
pp. L9
Author(s):  
T. Kojima ◽  
H. Kiuchi ◽  
K. Uemizu ◽  
Y. Uzawa ◽  
M. Kroug ◽  
...  
Keyword(s):  
High Speed ◽  
Quantum Noise ◽  
High Current Density ◽  
Noise Temperature ◽  
Intermediate Frequency ◽  
Submillimeter Wave ◽  
Low Noise ◽  
Sis Mixer ◽  
Receiver System ◽  
Wideband Radio

We report on a 275–500 GHz heterodyne receiver system in combination with a wideband intermediate-frequency (IF) backend to realize 17 GHz instantaneous bandwidth. The receiver frontend implements a heterodyne mixer module that integrates a superconductor-insulator-superconductor (SIS) mixer chip and a cryogenic low-noise preamplifier. The SIS mixer is developed based on high-current-density junction technologies to achieve a wideband radio frequency (RF) and IF bandwidth. The IF backend comprises an IF chain divided into two channels for 4.0–11.5 GHz and 11.3–21.0 GHz and an analog-to-digital converter (ADC) module that is capable of high-speed sampling at 32 Giga samples per second with 12.5 GHz bandwidth per channel and an effective number of bits of 6.5. The IF backend allows us to simultaneously cover the full 4–21 GHz IF range of the receiver frontend. The measured noise temperature of the receiver frontend was below three times the quantum noise (hf/kB) over the entire RF band. A dual-polarization sideband-separating receiver based on this technique could provide up to 64 GHz of instantaneous bandwidth, which demonstrates the possibility of future wideband radio astronomical observations with advanced submillimeter-wave heterodyne receivers.

Distribution of R- and S-Process Elements in the Galactic Halo

1988 ◽  
Vol 132 ◽  
pp. 501-506
Author(s):  
C. Sneden ◽  
C. A. Pilachowski ◽  
K. K. Gilroy ◽  
J. J. Cowan
Keyword(s):  
Heavy Element ◽  
Galactic Halo ◽  
Low Noise ◽  
Heavy Elements ◽  
Process Synthesis ◽  
Element Abundances ◽  
Halo Stars ◽  
Abundance Patterns ◽  
R Process ◽  
Process Elements

Current observational results for the abundances of the very heavy elements (Z>30) in Population II halo stars are reviewed. New high resolution, low noise spectra of many of these extremely metal-poor stars reveal general consistency in their overall abundance patterns. Below Galactic metallicities of [Fe/H] Ã −2, all of the very heavy elements were manufactured almost exclusively in r-process synthesis events. However, there is considerable star-to-star scatter in the overall level of very heavy element abundances, indicating the influence of local supernovas on element production in the very early, unmixed Galactic halo. The s-process appears to contribute substantially to stellar abundances only in stars more metal-rich than [Fe/H] Ã −2.

Microcalorimeters for X-Ray Spectroscopy

1988 ◽  
Vol 102 ◽  
pp. 41
Author(s):  
E. Silver ◽  
C. Hailey ◽  
S. Labov ◽  
N. Madden ◽  
D. Landis ◽  
...  
Keyword(s):  
High Resolution ◽  
High Efficiency ◽  
Thermal Response ◽  
Low Noise ◽  
High Resolution Spectroscopy ◽  
Superconducting Transition ◽  
Sapphire Substrates ◽  
Laboratory Plasmas ◽  
Adiabatic Demagnetization ◽  
Theoretical Predictions

The merits of microcalorimetry below 1°K for high resolution spectroscopy has become widely recognized on theoretical grounds. By combining the high efficiency, broadband spectral sensitivity of traditional photoelectric detectors with the high resolution capabilities characteristic of dispersive spectrometers, the microcalorimeter could potentially revolutionize spectroscopic measurements of astrophysical and laboratory plasmas. In actuality, however, the performance of prototype instruments has fallen short of theoretical predictions and practical detectors are still unavailable for use as laboratory and space-based instruments. These issues are currently being addressed by the new collaborative initiative between LLNL, LBL, U.C.I., U.C.B., and U.C.D.. Microcalorimeters of various types are being developed and tested at temperatures of 1.4, 0.3, and 0.1°K. These include monolithic devices made from NTD Germanium and composite configurations using sapphire substrates with temperature sensors fabricated from NTD Germanium, evaporative films of Germanium-Gold alloy, or material with superconducting transition edges. A new approache to low noise pulse counting electronics has been developed that allows the ultimate speed of the device to be determined solely by the detector thermal response and geometry. Our laboratory studies of the thermal and resistive properties of these and other candidate materials should enable us to characterize the pulse shape and subsequently predict the ultimate performance. We are building a compact adiabatic demagnetization refrigerator for conveniently reaching 0.1°K in the laboratory and for use in future satellite-borne missions. A description of this instrument together with results from our most recent experiments will be presented.

Sign in / Sign up

Export Citation Format

Share Document