Color tunable photoluminescence in KZABS: Tm3+ glasses under different sources of excitation for photonic applications

Potassium Zinc Alumino Borosilicate (KZABS) glasses doped with Tm ³⁺ ions have been prepared by using a melt quenching process and further investigated through various spectroscopic tools such as optical absorption, photoluminescence (PL) excitation, PL emission, and PL decay measurements. The non-crystalline nature of the as-prepared glasses was confirmed by XRD measurements. PL spectral properties show blue and red colors under different excitation wavelengths. The absorption spectrum recorded in the UV-Vis-NIR range reveals the high bandgap energy. The Inokuti-Hirayama (I-H) model well fitted to non-exponential decay curves confirms the energy transfer between Tm ³⁺-Tm ³⁺ ions as dipole-dipole in nature. Under 359 and 466 nm excitation wavelength the titled glasses are showing CIE coordinates falling in deep blue and deep red color, respectively. A good color tunability can be seen from the blue to the red region under different excitation wavelengths. All the studies finally reveal the superiority of Tm ³⁺ doped KZABS glasses for their usage in blue/red-emitting photonic devices needed to fabricate photonic devices such as w-LEDs.