Spectroscopic characterization of Er-1 center in selectively doped silicon

We report on investigation of Er-related optically excited emission from selectively doped Si/Si:Er nanolayer structures grown by sublimation MBE method. Results of high-resolution photoluminescence (PL) and magneto-optical spectroscopy are presented. We show that annealing of such samples results if a preferential formation a single type of optically active Er-related centers. This is concluded from a successful observation of the Zeeman effect of magnetic field induced splitting of the photoluminescence spectrum, labeled Er-1, associated with this center. We further show that the Er-1 spectrum is characterized by an ultra narrow bandwidth of less than 10 μeV, consistent with an assignment to a single type of centers. Consequences of this new development for future photonic applications of Si:Er are pointed out.