Method to extract the non-linear characteristics of high temperature superconducting (HTS) RF coils
Girard O, Ginefri J, Darrasse L
CNRS - Universite Paris Sud
High-temperature superconducting (HTS) surface coils can strongly improve the SNR in MR microscopy. However the implementation of such RF coils remains difficult since power levels involved during transmission lead to a non-linear response. This results in flip-angle misadjustements and severe shape distortion of slice-selective soft pulses. We describe here a method for complete RF coils characterization accounting for non-linear conduction. The non-linear characteristics is required to compensate for the undesirable effects and to help designing more convenient matching circuits or RF coils based on improved materials or geometries.