Molecular-beam-epitaxy grown GaBiAs for terahertz optoelectronic applications

GaBi (x) As1-x layers with compositions of 0 < x < 0.11 were grown on GaAs substrates by low-temperature molecular-beam-epitaxy. Energy bandgaps as narrow as 0.74 eV were documented in the layers with the largest Bi-content. This material is also characterized by very short, picosecond carrier lifetimes and is prospective for applications in optoelectronic terahertz radiation components activated by femtosecond pulses of near infrared lasers.