High-speed optical detectors in YBCO films with non-granular and fine-grain morphologies

Author

Tang, Q. ; Driessen, A. ; Hilderink, L.H. ; IJsselsteijn, R.P.J. ; Folkstra, J. ; Popma, T.J.A.

Author_Institution

Dept. of Appl. Phys., Twente Univ., Enschede, Netherlands

Volume

3

Issue

1

fYear

1993

fDate

3/1/1993 12:00:00 AM

Firstpage

2864

Lastpage

2868

Abstract

Optical detectors based on YBa/sub 2/Cu/sub 3/O/sub 7- delta / thin films have been fabricated, which show a response time of a few ns. Typical dimensions of the active area are 10 mu m*10 mu m. No preamplifier is needed during operation. The authors report on the optical response of detectors having nongranular and fine-grain morphologies to different sources of pulsed laser radiation (e.g., mode-locked Nd:YLF laser at 1.3 mu m and a GaAs diode laser at 0.9 mu m). Emphasis in the study is placed on detection sensitivity for measuring short optical pulses. It is found that the best noise obtained with a fine-grain detector is on the order of 10/sup -10/ W/Hz/sup 1/2/, when irradiated by the 65-ns-pulsewidth diode laser.<>

Keywords

barium compounds; high-temperature superconductors; photodetectors; superconducting junction devices; superconducting thin films; yttrium compounds; YBCO films; YBa/sub 2/Cu/sub 3/O/sub 7- delta /; detection sensitivity; fine-grain morphologies; high temperature superconductor; nongranular; optical detectors; short optical pulses; Delay; Diode lasers; High speed optical techniques; Laser mode locking; Laser noise; Optical detectors; Optical films; Optical pulses; Preamplifiers; Yttrium barium copper oxide;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/77.233999

Filename

233999