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

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.