Efficient Energy Transfer and Enhanced Near‐IR Emission in Cu+/Nd3+‐Activated Aluminophosphate Glass

Abstract

The development of photonic materials for efficient energy conversion and high‐power solid‐state lasers is currently pursued given the wide range of applicable technologies and the possibility to help meet global energy demands in laser fusion power plants. In this work, Cu+ ions successfully incorporated in aluminophosphate glass are recognized as near‐ultraviolet (UV) sensitizers of Nd3+ ions resulting in remarkable near‐infrared (IR) 4F3/2 → 4I11/2 emission at 1.06 μm. Optical absorption, solid‐state 31P nuclear magnetic resonance, Raman, and photoluminescence spectroscopies characterizations are employed and assessment methods for material optical and structural properties are proposed. The spectroscopic data indicates an efficient (>50%) nonradiative energy transfer where the Cu+ ions first absorb photons broadly around 360 nm, and subsequently transfer the energy from the Stokes‐shifted emitting states to resonant Nd3+ energy levels. Then, the Nd3+ electronic excited states decay and the upper lasing state 4F3/2 is populated, leading to enhanced near‐IR emission. It is suggested that the physico‐chemically robust Cu+/Nd3+ codoped aluminophosphate glass is a suitable candidate as solid‐state laser material with enhanced pump range in the near‐UV part of the spectrum and for solar spectral conversion in photovoltaic cells.