On relation between the 1.5 μm Er-related emission and 9 μm vibrational modes of oxygen in silicon

We demonstrate that excitation of Er3+ ions embedded in crystalline silicon is effectively quenched when vibrational modes of interstitial oxygen are activated. In a two-color pump–probe experiment with a free-electron laser, we show that the 1.5 μm Er-related photoluminescence diminishes as the probing beam scans through the relevant 9 μm absorption band. Making use of time resolution of the experimental set-up, we investigate temporal aspects of this effect.