Growth and characterization of GaBiAs epilayers

Abstract GaBiAs layers have been grown by molecular beam epitaxy at low temperatures (270–330 °C) and have been characterized with several experimental techniques. Linear absorption and photoluminescence measurements have shown that the energy band gap decreases, compared with GaAs, and may reach 0.88 eV, depending on growth conditions. An optical bleaching effect has been observed in open aperture z -scan measurements with saturation intensity values of 300–1000 MW/cm 2 at 1.054 μm. Optical pump–terahertz probe measurements of these layers have shown electron trapping time to decrease with decreasing growth temperature and reach 1 ps at the lowest growth temperatures. This has been confirmed by time-resolved photoluminescence measurements. The manufactured photoconductive terahertz emitters and detectors made from GaBiAs layers have demonstrated a signal bandwidth of 3.5 THz.