Laser application of Pb1-xSrxS films prepared by hot wall epitaxy
Pb1-xSrxS films and Pb1-xSrxS/PbS double-heterostructure lasers were prepared using a hot wall epitaxy technique. Pb1-xSrxS films with energy band gaps up to 1.1 eV (x=0.15) were obtained. The band gap increased very rapidly with the SrS content as dEg/dx=7.5 eV (x<0.04), while the lattice constant increased as da/dx=0.034aPbS. Impurity dopings were performed and electrical properties were measured for the Pb1-xSrxS films. Films with large p- or n-type concentrations were obtained by doping with Tl or Bi impurities. Pb1-xSrxS/PbS double-hetero diode lasers with broad area and stripe contacts were fabricated. Laser operations were obtained up to 210 K pulsed for the broad-area laser and 245 K pulsed (174 K cw) for the stripe contact laser around 3 mu m.