Surface resistance measurements of HTS thin films using SLAO dielectric resonator

Abstract

Surface resistance of HTS films is typically measured using Sapphire dielectric rod resonators enclosed in a copper cavity. In this paper we present surface resistance measurements of YBa 2 Cu 3 O 7 films using Strontium Lanthanum Aluminate (SLAO) at a resonant frequency of 18.2 GHz. We have performed the error analysis of the cavity loaded with SLAO dielectric rod and also verification measurements using two Sapphire (Al 2 O 3 ) rod resonators operating at resonant frequencies of 24.6 GHz and 10 GHz respectively. Good agreement between the values of of two sets of YBCO films measured using the SLAO and the Sapphire dielectrics has been obtained after a frequency scaling of was applied. Using different dielectric rods of the same size in the same cavity for measurements of of HTS films it is feasible to do microwave characterization of the same films at differing frequencies.Index Terms-Dielectric resonator, high temperature superconductor, surface resistance.

Dielectric resonator method for determining gap symmetry of superconductors through anisotropic nonlinear Meissner effect

“…Consistency check for gap nodal structure with low temperature surface impedance measurement Although examining the anisotropy of the LSM-PR is sensitive to the gap nodal properties of the superconducting samples of interest, the deduced symmetry is further confirmed by a consistency check from low temperature surface impedance measurements. 27,38,39,[46][47][48][49][50][51][52][53][54][55] In this case, the input and output microwave signals are generated and received by the Keysight vector network analyzer N5242A and the laser is turned off. The transmission lines for the microwave signal are calibrated down to the input/output ports of the dielectric resonator (p1, p2 in Fig.4) with an in-situ cryogenic calibration technique.…”

High-Temperature Measurement Technology for Microwave Surface Resistance of Metal Materials

“…For the former, part of the cavity wall is replaced with a metal under test (MUT), and the change in quality factor of the cavity before and after replacement can be used to extract the MSR of the MUT. For the latter, a low loss cylindrical medium (such as a sapphire) is placed on a single MUT plate (open-ended) or between two MUT plates (Hakki-Coleman's geometry), and the MSR of the MUT plate is calculated according to the measured quality factor and the known complex permittivity of the cylindrical medium; these methods have been widely used in the measurement of the MSR of graphene sheets, superconducting films, semiconductors, and copper clad laminates [19][20][21][22][23]. However, the above methods and systems are all used to measure the MSR of metal materials at room temperature, and there are currently no reports of high-temperature MSR measurement in the literature.…”

Liftoff Dielectric Resonator for the Microwave Surface Resistance Measurement of Metal Plates

“…must be evaluated before any measurements can be made. Manufacturer values for the dielectrics loss tangent are sometimes used directly [18], and if known high temperature superconducting (HTS) film standards are available, these values can be verified [15]. More commonly the dielectric is measured in isolation using methods such as high order, quasi-TE 0mn modes [20] or whispering gallery modes [16].…”