Ultra-broadband infrared luminescence of Bi-doped thin-films for integrated optics

Abstract

Ultra-broadband infrared luminescence has been observed in bismuth (Bi)-doped germanate thin-films prepared by pulsed laser deposition. The films are compatible with various types of substrates, including conventional dielectrics (LaAlO₃, silica) and semiconductors (Si, GaAs). The emission peak position of the films can be finely tuned by changing oxygen partial pressure during the deposition, while the excitation wavelength locates from ultra-violet to near-infrared regions. The physical mechanism behind the observed infrared luminescence of the Bi-doped films, differing from that of the as-made glass, is discussed.