Electrical and Thermal Modulation of the Propagation Time in Superconducting Spiral Lines by Optoelectronic Techniques

초록

Current and temperature controlled delays in the propagation time of electrical pulses in YBaCuO(YBCO) spiral transmission lines have been investigated by using optoelectronic techniques. The transmission lines are configured in a stripline geometry, where the central strip consists of a thin film of YBCO embedded in LaAlO3. The propagation time of electrical pulses through the spiral transmission lines is measured using electrical autocorrelation techniques making use of semiconductor optical switches. The measured propagation time shows a quadratic dependence on the applied current, which is in good agreement with the Ginzburg-Landau theory. As the temperature increases, a gradual increase in pulse width and a delay in the propagation time of electrical pulses are observed. The results are used to determine the actual temperature-dependent function of the magnetic penetration depth of YBCO spiral lines.