Anomalous near-infrared emission and the underlying “structure-luminescence” correlation in the multi-peak emission system of KScF 4 :Yb 3+ ,Mn 2+

Anomalous broadband NIR emission (both in Stokes and UC) is achieved in KScF 4 :Yb 3+ ,Mn 2+ phosphor, which is attributed to the super-exchange coupled Mn Sc1 –Mn Sc2 dimers. This phosphor has application prospects in night vision, bio-imaging, etc .