Coupling of Erbium-Implanted Silicon to a Superconducting Resonator

Abstract

Erbium-implanted silicon is promising for both photonic and quantum-technology platforms, since it possesses both telecommunications and integrated-circuit processing compatibility. However, several different Er centers are generated during the implantation and annealing process, the presence of which could hinder the development of these applications. When Si is coimplanted with 1017cm-3 Er and 1020cm-3 O ions, and the appropriate annealing process is used, one of these centers, which is present at higher Er concentrations, can be eliminated. Characterization of samples with Er concentrations of <1017cm-3 is limited by the sensitivity of standard electron paramagnetic resonance (EPR) instruments. The collective coupling strength between a superconducting (SC) NbN lumped-element resonator and a 1017cm-3 Er-implanted Si sample at 20 mK is measured to be about 1 MHz, which provides a basis for the characterization of low-concentration Er-implanted Si and for future networks of hybrid quantum systems that exchange quantum information over the telecommunication network. Of six known Er-related EPR centers, only one trigonal center couples to the SC resonator.