PROBLEM TO BE SOLVED: To provide a superconductor using surface superconductivity; an accurate, easy and inexpensive noncontact measurement method for superconductor surface resistivity using an alternating electric field generated with surface acoustic waves; and its measurement apparatus. SOLUTION: In this noncontact measurement method for superconductor surface resistivity, in a flat piezoelectric element 13 having input and output electrode pairs 11 and 12 on both sides, a gap 48 is formed to arrange a superconductor 14; while surface acoustic waves generated by an input voltage applied to the input electrode pair 11 is being moved toward the output electrode pair 12, an alternating electric field accompanying the surface acoustic waves is applied to the superconductor 14, and the surface resistivity of the superconductor is determined from the value of the ratio between an output voltage value detected by the output electrode pair 12 and an input voltage component value corresponding to the frequency of the elastic surface waves in the input voltage. A pulse voltage is used as the input voltage, and the output voltage value and the input voltage component value are determined from the individual fast Fourier transformation of the output voltage measured by the output electrode pair 12 and the input voltage. The frequency of the elastic surface waves is set within the range, in which the alternating electric field is reflected on the surface of the superconductor 14 so that the field does not enter the inside. COPYRIGHT: (C)2009,JPO&INPIT
