Millimeter Wave Transmission Studies of YBa2Cu3O7−δ Thin Films in the 26.5 to 40.0 GHz Frequency Range
Millimeter wave transmission measurements through YBa2Cu3O7−δ thin films on MgO, ZrO2 and LaA1O3 substrates, are reported. The films (0.2 to 1.0 μm) were deposited by sequential evaporation and laser ablation techniques. Transition temperatures Tc, ranging from 89.7 K for the laser ablated film on LaA1O3 to approximately 72 K for the sequentially evaporated film on MgO, were obtained. The values of the real and imaginary parts of the complex conductivity, σ1 and σ2, are obtained from the power transmitted through the film, assuming a two fluid model. The magnetic penetration depth is evaluated from the values of σ2. These results will be discussed together with the frequency dependence of the normalized transmission amplitude, P/Pc, below and above Tc.
KeywordsLaser Ablation Fluid Model Microwave Absorption Versus Temperature Complex Conductivity
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- 1.Hartwig, W.; and Passow, C.: RF Superconducting Devices -- Theory, Design, Performance, and Applications. Applied Superconductivity, vol. 2, V.L. Newhouse, ed., Academic Press, New York, 1975, pp. 541–639.Google Scholar
- 3.Carini, J.P., et al.: Millimeter-Wave Surface Resistance Measurements in Highly Oriented YBa2Cu3O7-δ Thin Films. Phys. Rev. B, vol. 37, no. 16, 1 June 1988, pp. 9726–9729.Google Scholar
- 6.Sridhar, S.; Shiffman, C.A.; and Handed, H.: Electrodynamic Response of YlBa2Cu3Oy and La1.85Sr0.15CuOu-s in the Superconducting State. Phys. Rev. B, vol. 36, no. 4, 1 Aug. 1987, pp. 2301–2304.Google Scholar
- 7.Cohen, L., et al.: Surface Impedance Measurements of Superconducting YBa2Cu3O6+x. J. Phys. F: Met. Phys., vol. 17, 1987,, pp. L179–L183.Google Scholar
- 9.Nichols, C.S., et al.: Microwave Transmission Through Films of YBa2Cu3O7.4. To be published in Phys. Rev. B.Google Scholar
- 13.Gittleman, J.I.; and Bozowski, S.: Transition of Type-I Superconducting Thin Films in a Perpendicular Magnetic Field: A Microwave Study. Phys. Rev., vol$1161, no. 2, 10 Sept., 1967, pp. 398–403.Google Scholar
- 15.Tyagi, S., et al.: Frequency Dependence of Magnetic Hysteresis in the Field-Induced Microwave Absorption in High-Tc Superconductors at T Tc. To be published in Phys. Lett. A.Google Scholar
- 16.Jackson, E.M., et al.: Study of Microwave Power Absorption in Yttrium-Barium-Copper Based High Temperature Superconductors and Allied Compounds. To be published in Supercond. Sci. Technol.Google Scholar
- 19.J.D. Warner, J.E. Meola and K.A. Jenkins:“Study of Deposition of YBa2Cu3O7-x on Cubic Zirconia,” NASA TM-102350 (1989).Google Scholar
- 20.G.J. Valco, N.J. Rohrer, J.D. Warner and K.B. Bhasin:“Sequentially Evaporated Thin Y-Ba-Cu-O Superconducting Films on Microwave Substrates” NASA TM-102068 (1989).Google Scholar
- 21.Miranda, F.A., et al.: Measurements of Complex Permittivity of Microwave Substrates in the 20 to 300 K Temperature Range From 26.5 to 40.0 GHz. NASA TM-102123, 1989.Google Scholar
- 24.Kobrin, P.H., et al.: Millimeter-Wave Complex Conductivities of Some T1BaCaCuO and YBa2Cu3O7-f Films, Presented at the M2s-HTSC Conference, Stanford, CA, July 24–28, 1989. To be published in Physica C.Google Scholar