Title :
High-Tc ramp-type Josephson junctions on MgO substrates for terahertz applications
Author :
Myoren, H. ; Verhoeven, M.A.J. ; Jian Chen ; Nakajima, K. ; Yamashita, T. ; Blank, D.H.A. ; Rogalla, H.
Author_Institution :
Res. Inst. of Electr. Commun., Tohoku Univ., Sendai, Japan
Abstract :
The authors successfully fabricated high-Tc ramp-type junctions with PrBa/sub 2/Cu/sub 3-x/Ga/sub x/O/sub 7-/spl delta// (PBCGO: x=0.1, 0.4) barriers on MgO substrates. The junctions showed resistively shunted Josephson junction (RSJ)-like I-V curves with thermally and voltage activated conductivity. The I/sub c/R/sub n/ products for these junctions scaled very well with the Ga-doping. Maximum response of the junctions for 100-GHz millimeter-wave irradiation could be observed up to 12 mV corresponding to 6 THz. Using far infrared laser radiation, we confirmed a terahertz (THz) response of these junctions. These results show promise for THz-wave applications of ramp-type Josephson junctions.
Keywords :
Josephson effect; barium compounds; high-temperature superconductors; praseodymium compounds; 100 GHz; 6 THz; Ga doping; MgO; MgO substrate; PBCGO barrier; PrBa/sub 2/(CuGa)/sub 3/O/sub 7/; far infrared laser irradiation; high-Tc ramp-type Josephson junction; millimeter wave irradiation; resistively shunted junction; terahertz response; Dielectric constant; Dielectric losses; Dielectric substrates; Finite impulse response filter; Frequency; High temperature superconductors; Josephson junctions; Physics; Superconducting photodetectors; Thermal conductivity;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
