YBCO superconducting ring resonators at millimeter-wave frequencies

Terahertz Pioneer: Tatsuo Itoh “Transmission Lines and Antennas: Left and Right”

“…Another THz focused journal did not appear until September 2011, when this publication, IEEE TRANSACTIONS ON TERAHERTZ SCIENCE AND TECHNOLOGY released its Inaugural Issue. range of other microwave and millimeter-wave topics including superconducting circuits and devices [114]- [116], high speed photodetectors [117], new transmission line structures [118] and components [119], wireless circuits and antennas [120]- [122], and of course, dozens of analytic methods papers of which [123] is just one example.…”

Correction factor for determining the London penetration depth from strip resonators

“…Determiningc(T) is not so straightforward but it can be estimated from [3] where resonant frequency versus temperaturedata was provided for a metallic conductor on LaAIO3. Ae(T) was taken as -550 ppm/K which is an order 2 of magnitude more severe than results disclosed in [4].…”

“…For most practicalmicrowave applications, line impedanceswill be in the neighborhood of 50 f_, and film thickness will be of the same order as the penetration depth. Experimental investigations using strip transmission lines near Tc have invariably revealed a strong deviation from theory [3][4][5] when t = _,.This short paper shows that the disagreement can be attributed, at least in part, to the susceptance coupled into the resonator from the gap discontinuity as well as the feed line of electrical length [31. The coupled susceptance is modifiedby the temperature dependent characteristic impedance of the resonator.…”

Resonance of High Tc Superconducting Microstrip Patch in a Substrate-Superstrate Configuration

“…Passive planar supeconductor circuits such as transmission lines, filters, and resonators have shown substantial improvement over identical circuits fabricated with gold, silver, or copper metallization [4][5][6][7]. The demonstration of practical microwave circuits utilizing high-temperature superconductors has prompted investigations into how high-temperature superconductors may be used in antenna systems [8][9][10][11].…”