Energy transfer-induced blue light-excited broadband near-infrared luminescence in fluoride Na3AlF6:Mn4+,Fe3+

Blue-light excited near-infrared luminescence was demonstrated in Na 3 AlF 6 :Mn 4+ ,Fe 3+ via Mn 4+ → Fe 3+ ET. Upon 463 nm excitation, narrowband emissions from Mn 4+ and broadband emission peaked at 826 nm with FWHM of 127 nm from Fe 3+ were realized.