Novel dilute InPBi for IR emitters

InPBi crystalline thin films with a bismuth concentration up to 4.8% have been successfully grown using molecular beam epitaxy for the first time. This novel material reveals strong and broad photoluminescence in the wavelength range of 1-2.5 μm at room temperature, although the absorption measurements point out a near band-gap absorption character. Various structural and optical characterization techniques are used to assess material quality and to understand the physical origins of the unexpected light emission. The InPBi is almost lattice matched to InP, making such a material very promising for InP based optoelectronics devices. The emitted light covers the telecom wavelength regime as well as other important wavelengths for gas sensing. The very broad emission spectrum of more than 600 nm promises for making super-luminescence IR diodes that have potentials to significantly enhance the spatial resolution in optical coherence tomography (OCT).