Fig. 1: Programmable quantum emitter formation with femtosecond (fs) laser pulses in silicon-on-insulator (SOI).
Artistic representation of the fs laser irradiation approach to locally write and erase G, and Ci centers in SOI. The G center is a pair of two carbon atoms at substitutional sites (black sphere) combined with the same Si self-interstitial (pink sphere), whereas the Ci consists of a pair of an interstitial carbon (green sphere) and a substitutional Si atom (gray sphere) in the Si lattice. A single fs laser pulse (pulse duration of 90 fs), with wavelength centered at 800 nm, was used for irradiation at varied fluences to locally form and erase quantum emitters. Three different areas are highlighted to represent the workflow starting with a pre-processed SOI wafer with ensemble Ci centers formed after ion implantation and rapid thermal annealing under forming ambiance (area on the left). The second area (in the middle) represents the writing of G centers along with modified Ci centers on the pre-processed SOI sample via single fs laser pulse irradiation at relatively low fluences (<30 mJ/cm2). The third area (on the right) shows the erasing of quantum emitters after irradiation with a relatively higher laser fluence (still much below the melting threshold for Si). A photoluminescence hyperspectral scan with fs laser pulse irradiation spots processed at a fluence of 12 mJ/cm2 is shown in the top-right corner.
