Terahertz response for bicrystal YBCO Josephson junctions

Author

Nakajima, K. ; Jian Chen ; Myoren, H. ; Yamashita, T. ; Peiheng Wu

Author_Institution

Res. Inst. of Electr. Commun., Tohoku Univ., Sendai, Japan

Volume

7

Issue

2

fYear

1997

fDate

6/1/1997 12:00:00 AM

Firstpage

2607

Lastpage

2610

Abstract

The high-frequency response of bicrystal YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// Josephson junctions for far infrared laser irradiation is presented. The junctions on silicon and MgO substrates exhibit a remarkable first order Shapiro step for the methanol line at 1.76 THz. dV/dI measurements reveal several steps corresponding to the methanol lines at 1.48, 1.76 and 2.53 THz. The line width of Josephson oscillation at these frequencies is estimated from the width of the Shapiro steps. It is suggested that the excess shot noise broadens the line width.

Keywords

Josephson effect; barium compounds; grain boundaries; high-temperature superconductors; laser beam effects; oscillations; shot noise; submillimetre wave detectors; superconducting device noise; superconducting junction devices; superconducting particle detectors; yttrium compounds; 1.48 to 2.52 THz; FIR laser irradiation; Josephson oscillation; MgO; MgO substrate; Shapiro steps; Si; Si substrate; YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta//; YBa/sub 2/Cu/sub 3/O/sub 7/-MgO; YBa/sub 2/Cu/sub 3/O/sub 7/-Si; bicrystal YBCO Josephson junctions; excess shot noise; far infrared laser irradiation; high-frequency response; line width; methanol lines; terahertz response; Finite impulse response filter; Frequency estimation; Grain boundaries; Josephson junctions; Methanol; Pump lasers; Semiconductor films; Silicon; Voltage; Yttrium barium copper oxide;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/77.621773

Filename

621773