EPR RESONATOR WITH EXTENDED TRANSPARENCY AND HOMOGENEITY IN RF RANGE

摘要

An EPR resonator for a cylindrical TE01 n microwave mode where n is an integer, in particular from 1 to 4, comprises: a cylindrical body (10) which has an RF absorption of less than 5% at RFs below 1 kHz, a first plunger (11) delimiting the resonating volume within the cylindrical body in an axial direction at a first end and a second plunger (12) delimiting the resonating volume within the body at a second end, the second plunger having an opening (13) for inserting an EPR sample into the resonator. The resonator is characterized in that the first and the second plunger each comprise a spiral winding of an electrically conductive filament wherein neither the ends nor neighboring turns of the spiral windings have electrically conductive connections which could lead to a formation of electrically closed loops. The use of spiral winding plungers for cylindrical TE01 n microwave modes provides equivalent functionality compared to state of the art plungers, but without creating Eddy currents at frequencies lower than the frequency of the TE01 n microwave mode.