We report a new contactless technique for material characterization - magnetic-field-modulated microwave reflectivity (MFMMR). The technique is based on a microwave scanning probe integrated with an inductive coil. The coil produces an ac magnetic field which modulates the microwave reflectivity of the sample. The technique is spatially-selective and is capable to detect several superconducting phases in a multiphase sample and to localize minute quantities of superconductor in a nonsuperconducting matrix. The technique may be an useful asset for the computerized search of new superconducting and magnetoresistive compounds obtained via combinatorial synthesis, since it allows an automatic recognition of magnetic-field sensitive phase transitions.
展开▼
