Room Temperature NUV‐To‐NIR Up‐ and Down‐Conversion Photoluminescence in Erbium‐Doped GaAs

Abstract Erbium (Er)‐doped III‐V semiconductors are promising for optoelectronic devices due to the unique intra‐4f electronic transitions of Er³⁺; however, the Er‐related luminescence at room temperature has always been challenging to obtain. In this work, High crystalline quality ErAs:GaAs films are grown with self‐assembled ErAs nanoparticles embedded within the GaAs matrix by molecular beam epitaxy. Rich photoluminescence spectra in a broad wavelength ranging from near‐ultraviolet to near‐infrared are observed at room temperature and confirmed to be Er‐related. A carrier‐mediated energy transfer up‐conversion mechanism is proposed, and the pump power‐dependent photoluminescence results reveal that the excited‐state absorption is governed by a single photonic process. The efficient interaction and energy transfer between the semiconductor matrix and Er³⁺ ions offered by this unique nanocomposite material provide a promising route to achieve novel optoelectronic devices with the potential to cover a broad wavelength range.