Magnetic field induced extraordinary photoluminescence enhancement in Er3+:YVO4 single crystal

A bright green photoluminescence (PL) from 4S3∕2 → 4I15∕2 emission band in Er3+:YVO4 single crystal has been observed with the excitation of an argon laser at 488.0 nm. More than two orders of PL enhancement have been obtained under the effect of magnetic fields, and the enhancement factor f reaches 170 when the applied magnetic field is 7.7 T under the sample temperature of 4.2 K. Unusually, the PL enhancements only happen at some certain magnetic fields (Bcs), and a decrease of sample temperature will lead to the increase of f and decrease of Bc. The results confirm that this PL enhancement originates from the resonance excitation of the electron transitions induced by the cross of the laser energy and the absorption energy modulated by both the magnetic field and temperature. This special PL enhancement in Er3+:YVO4 single crystal can be applied in the calibration of pulsed high magnetic field, detection of material fine energy structures, and modulation of magneto-optical devices.