Isotopic Fingerprints of four and five-atom Pt luminescence centers in $^{28}$Si

We have recently demonstrated that observing `isotopic fingerprints' in $^{28}$Si leads to many surprises regarding the actual constituents of supposedly well known deep luminescence centers. A series of four and five-atom complexes containing Cu, Ag, Au and Li were found. We now extend this by observing Pt containing centers in $^{28}$Si. The two previously observed Pt-related centers, with luminescence at 884 and 777 meV, are found to contain three and four Cu atoms, respectively, in addition to a single Pt atom. With the addition of Li to these Pt implanted samples we report on a series of four and five-atom complexes containing Cu, Pt and Li, similar to those found for Cu, Au and Li before. This further demonstrates the ubiquity of four- and five-atom luminescence centers in Si.