Title :
Quantum detectors in superconducting YBCO
Author :
Bluzer, N. ; Forrester, M.G.
Author_Institution :
Westinghouse Advanced Technol. Labs., Linthicum, MD, USA
fDate :
6/1/1995 12:00:00 AM
Abstract :
A superconducting quantum detector structure in YBCO is described with a directly coupled SQUID read out circuit. The detector geometry is optimized for maximum photoresponse with the use of a serpentine pattern. The serpentine pattern reduces quasiparticle diffusion effects and maximizes the photoinduced changes in the kinetic inductance. The operation of this sensor is analyzed in terms of geometry and quasiparticle lifetime to obtain expressions for the signal and noise of this detector. The background limited infrared performance of this detector is calculated to be about 5/spl times/10/sup -17/ NEP. The photoresponse is expected to be limited by the superconducting energy gap, about 30-40 /spl mu/m.<>
Keywords :
barium compounds; high-temperature superconductors; infrared detectors; superconducting devices; yttrium compounds; 30 to 40 micron; YBCO; YBaCuO; directly coupled SQUID read out circuit; infrared sensor; kinetic inductance; noise eqiuvalent power; photoresponse; quasiparticle diffusion; quasiparticle lifetime; serpentine pattern; superconducting energy gap; superconducting quantum detector; Coupling circuits; Geometry; Inductance; Infrared detectors; Kinetic theory; SQUIDs; Signal analysis; Superconducting device noise; Superconducting photodetectors; Yttrium barium copper oxide;
Journal_Title :
Applied Superconductivity, IEEE Transactions on