Described herein are improved configurations for a resonator for wireless power transfer that includes a conductor forming one or more loops and having an inductance L, a network of capacitors, having a capacitance, C, and a desired electrical parameter, coupled to the conductor, the network having at least one capacitor of a first type with a first temperature profile of the electrical parameter, and the network having at least one capacitor of a second type with a second temperature profile of the electrical parameter.